Wastewater Treatment Process Assessment

What is the primary function of the collection system in wastewater treatment?

• To treat water with chemicals

• To store wastewater indefinitely

• To transport wastewater through underground pipes

• To remove large debris from water

Answer explanation

The primary function of the collection system in wastewater treatment is to transport wastewater through underground pipes to treatment facilities, ensuring efficient and safe movement of sewage.

During preliminary treatment, which materials are removed from wastewater?

• Dissolved organic matter

• Large objects like sticks and plastic

• Oils and grease

• Harmful bacteria

Answer explanation

During preliminary treatment, large objects like sticks and plastic are removed from wastewater to prevent damage to equipment and ensure effective treatment. Other materials like dissolved organic matter and harmful bacteria are addressed in later stages.

What percentage of suspended solids is removed during primary treatment?

• 40%

• 50%

• 60%

• 70%

Answer explanation

During primary treatment, approximately 60% of suspended solids are removed from wastewater. This process primarily involves sedimentation, which effectively reduces the solid content.

Which process in wastewater treatment uses beneficial microorganisms to clean the water?

• UV disinfection

• Primary treatment

• Preliminary treatment

• Secondary treatment

Answer explanation

Secondary treatment uses beneficial microorganisms to break down organic matter in wastewater, effectively cleaning the water. This process is essential for reducing pollutants before the water is released or further treated.

What is the purpose of UV disinfection in wastewater treatment?

• To remove solid waste

• To eliminate harmful bacteria

• To separate oils from water

• To filter large debris

Answer explanation

The purpose of UV disinfection in wastewater treatment is to eliminate harmful bacteria, ensuring that the treated water is safe for discharge or reuse. This process does not remove solid waste, oils, or large debris.

How are biosolids typically used after treatment?

• They are disposed of in landfills

• They are released into rivers

• They are used in agriculture and land reclamation

• They are stored indefinitely

Answer explanation

Biosolids are nutrient-rich organic materials resulting from wastewater treatment. They are typically used in agriculture and land reclamation to improve soil quality and support plant growth, making this the correct choice.

What is the length of the sanitary pipe network in Calgary?

• 3,200 km

• 3,800 km

• 4,300 km

• 4,800 km

Answer explanation

Calgary's sanitary pipe network spans 4,300 km, making it the correct choice among the options provided. This extensive network is crucial for the city's wastewater management.

Which stage of treatment relies primarily on gravity to separate materials?

• UV disinfection

• Secondary treatment

• Primary treatment

• Preliminary treatment

Answer explanation

Primary treatment relies on gravity to separate solids from liquids in wastewater. This stage allows heavier materials to settle at the bottom, effectively removing a significant portion of suspended solids.

What is one key advantage of using UV disinfection?

• It requires minimal maintenance

• It is the cheapest method

• It removes all chemicals

• It adds nutrients to water

Answer explanation

One key advantage of UV disinfection is that it requires minimal maintenance compared to other methods. This makes it a convenient choice for ensuring water safety without frequent upkeep.

How many people does Calgary's wastewater system serve?

• Over 1.1 million

• Over 1.2 million

• Over 1.3 million

• Over 1.4 million

Answer explanation

Calgary's wastewater system serves over 1.3 million people, making it a crucial infrastructure for the city's sanitation and environmental management.