NCEES Environmental Engineering PE Exam

Question 1

On the NCEES PE Environmental exam, which process is used in a conventional drinking water treatment plant to remove suspended particles after coagulation and flocculation?

Accepted Answer

Sedimentation (clarification)

Answer

Reverse osmosis

Answer

Ion exchange

Answer

Ultraviolet disinfection

Question 2

In the NCEES PE Environmental exam, what does 'BOD5' measure in wastewater analysis?

Accepted Answer

The amount of dissolved oxygen consumed by microorganisms decomposing organic matter in 5 days at 20°C

Answer

Biological oxygen demand of soil samples over 5 years

Answer

The pH change over 5 days of aerobic treatment

Answer

The concentration of total dissolved solids after 5-day settling

Question 3

For the NCEES PE Environmental exam, what is the primary purpose of chlorination in drinking water treatment in the US?

Accepted Answer

To inactivate pathogenic microorganisms and provide residual disinfection in the distribution system

Answer

To remove heavy metals such as lead and arsenic

Answer

To soften hard water by precipitating calcium

Answer

To remove taste and odor compounds

Question 4

On the NCEES PE Environmental exam, what is the 'hydraulic retention time (HRT)' of a wastewater treatment reactor?

Accepted Answer

The average time water (liquid) spends in the reactor, equal to volume divided by flow rate

Answer

The time solids remain in the reactor before wasting

Answer

The time between backwash cycles in a filter

Answer

The contact time for disinfection

Question 5

In the NCEES PE Environmental exam, which US regulation sets National Primary Drinking Water Regulations (NPDWRs)?

Accepted Answer

Safe Drinking Water Act (SDWA)

Answer

Clean Water Act (CWA)

Answer

Resource Conservation and Recovery Act (RCRA)

Answer

Comprehensive Environmental Response Act (CERCLA)

Question 6

For the NCEES PE Environmental exam, what is 'eutrophication' of a water body caused by?

Accepted Answer

Excessive nutrient (nitrogen and phosphorus) loading stimulating algal growth and depleting oxygen

Answer

Acid mine drainage lowering pH

Answer

Heavy metal contamination from industrial discharge

Answer

Thermal pollution from power plant cooling water