APES Chapter 14 Notes: Water Pollution

Module 41: Wastewater from Humans and Livestock

I. Wastewater Problems

A. General Terms

• Pollutant: Causes unclean, impure conditions threatening organisms' health and the environment.
• Water Pollutant: Chemical, biological, or physical changes in water quality harmful to living organisms (Biodegradable vs. Nonbiodegradable).
• Sources of Water Pollution:
  • Point Sources: Specific sites like pipes, ditches, sewers; easy to locate and monitor.
  • Nonpoint Sources: Broad, diffuse; hard to trace (runoff, surface flow).
• Wastewater: Water from human and livestock activities.
• Types of Water Pollution:
  • Pathogens: From waste, cause diseases (e.g., E. coli).
  • Organic Wastes: Leaves, trash; deplete oxygen.
  • Chemical Pollutants: Inorganic materials, heavy metals, radioactive isotopes.
  • Sediments: Cloudy water, disrupts ecosystems.
  • Nutrients: Nitrates, phosphates causing eutrophication.
  • Thermal Pollution: Heat from industrial cooling raises water temperature.
  • Genetic Pollution: Non-native species disrupting ecosystems.

B. Oxygen Demand

• Dissolved Oxygen (DO): Essential for aquatic life; low levels cause stress.
• Biological Oxygen Demand (BOD): Oxygen needed by decomposers to break down organic material.
• Chemical Oxygen Demand (COD): Oxygen used when organic matter breaks down chemically.
• Hypoxia: Low oxygen zones, often caused by nitrogen runoff leading to phytoplankton blooms.

C. Nutrients

• Phosphorus: Vital for growth, but excess leads to eutrophication.
• Nitrogen Compounds: Inorganic forms like nitrate and ammonia; can cause oxygen depletion and health issues (e.g., "blue baby" syndrome).
• Eutrophication: Overenrichment of water bodies, often human-induced, leading to excessive plant growth and oxygen depletion.

II. Wastewater Treatment

A. History of Sewage Management

• Development from basic waste management in ancient times to advanced plumbing and sewage systems in modern times.

B. Septic Systems

• Components: Septic tank and leach field for onsite household wastewater treatment.
• Pros and Cons: Gravity-powered but requires maintenance.

C. Sewage Treatment Plants

• Stages:
  • Preliminary Treatment: Removal of debris and grit.
  • Primary Treatment: Separation of solids and grease.
  • Secondary Treatment: Biological breakdown of organic matter.
  • Tertiary Treatment: Removal of specific pollutants like nutrients.
• Sludge Treatment: Stabilization and reduction of sludge volume.

D. Legal Sewage Dumping

• Occurs when sewage infrastructure is overwhelmed.
• Causes environmental damage and health risks.

E. Feed Lots and Manure Lagoons

• Manure Lagoons: Used for livestock waste management; potential for leakage.

Module 42: Heavy Metals and Other Chemicals

I. Heavy Metals

• Toxic Metals: Cadmium, mercury, lead, etc.
• Environmental Distribution: Leaching, fossil fuel combustion, industrial discharge.
• Health Effects: Acute and chronic impacts including cancer, organ damage.

II. pH Issues

• Acid Deposition: Acid rain and dry deposition affecting ecosystems.
• Chemical Causes: Nonmetal oxides form acids when combined with water.
• Environmental Impact: pH affects toxicity of various elements.

III. Synthetic Organic Chemicals

• Includes pesticides, pharmaceuticals, industrial compounds.

IV. Chlorides

• Impact: Essential in small amounts but harmful in excess; affects water taste and aquatic life.

V. Total Iron

• Importance: Required by organisms; impacts water taste and industrial use.

VI. Water Temperature

• Human activities should maintain natural temperature ranges to protect ecosystems.

Module 43: Oil Pollution

I. Sources of Oil Pollution

• Accidents, drilling, natural seeps.

II. Oil Spill Remediation

• Manual cleaning, containment booms, surfactants, and engineered bacteria.

Module 44: Water Pollution Laws

I. Clean Water Act of 1972

• Establishes regulation framework and EPA authority over water pollutants.

II. Safe Drinking Water Act of 1974

• Sets standards for safe drinking water quality.