NEWEST CERTIFIED ENVIRONMENTAL
SCIENTIST CERTIFICATION EXAM OFFERED
BY THE NATIONAL REGISTRY OF
ENVIRONMENTAL PROFESSIONALS |
COMPLETE EXAM Q&A WITH RATIONALES
1. Which federal law regulates the release of
hazardous substances into the environment and
authorizes cleanup of contaminated sites?
A) Clean Air Act
B) Clean Water Act
C) Comprehensive Environmental Response,
Compensation, and Liability Act (CERCLA)
D) Toxic Substances Control Act
Correct answer: C
Rationale: CERCLA, also known as Superfund,
provides federal authority to respond directly to
releases of hazardous substances and to compel
responsible parties to clean up contaminated sites.
2. The pH of normal, unpolluted rainwater is
approximately:
A) 4.0
,B) 5.6
C) 7.0
D) 8.2
Correct answer: B
Rationale: Carbon dioxide in the atmosphere
dissolves in rainwater to form carbonic acid,
resulting in a natural pH of about 5.6.
3. Which of the following is a primary pollutant that
directly contributes to the formation of
photochemical smog?
A) Carbon dioxide
B) Nitrogen oxides (NOx)
C) Methane
D) Chlorofluorocarbons
Correct answer: B
Rationale: Nitrogen oxides react with volatile organic
compounds in the presence of sunlight to form
ground-level ozone and photochemical smog.
4. The layer of the atmosphere that contains the
majority of Earth's weather phenomena is the:
A) Troposphere
,B) Stratosphere
C) Mesosphere
D) Thermosphere
Correct answer: A
Rationale: The troposphere extends from Earth's
surface to about 8-15 km and contains approximately
80% of atmospheric mass and most water vapor,
making it the site of virtually all weather.
5. Which hazardous waste characteristic is defined
as having a pH less than 2 or greater than 12.5?
A) Ignitability
B) Corrosivity
C) Reactivity
D) Toxicity
Correct answer: B
Rationale: Corrosive wastes are acidic (pH ≤2) or
alkaline (pH ≥12.5) and can destroy living tissue or
corrode metal containers.
6. The primary cause of eutrophication in freshwater
systems is excess:
A) Heavy metals
, B) Suspended solids
C) Nitrogen and phosphorus
D) Dissolved oxygen
Correct answer: C
Rationale: Excess nitrogen and phosphorus from
agricultural runoff, sewage, and detergents stimulate
algal blooms, leading to oxygen depletion and
ecosystem degradation.
7. Which US federal agency is primarily responsible
for protecting human health and the environment?
A) OSHA
B) EPA
C) FDA
D) DOI
Correct answer: B
Rationale: The Environmental Protection Agency
(EPA) was established in 1970 to enforce
environmental laws and regulate pollutants.
8. A confined aquifer is best described as:
A) An aquifer that is partially filled with water
SCIENTIST CERTIFICATION EXAM OFFERED
BY THE NATIONAL REGISTRY OF
ENVIRONMENTAL PROFESSIONALS |
COMPLETE EXAM Q&A WITH RATIONALES
1. Which federal law regulates the release of
hazardous substances into the environment and
authorizes cleanup of contaminated sites?
A) Clean Air Act
B) Clean Water Act
C) Comprehensive Environmental Response,
Compensation, and Liability Act (CERCLA)
D) Toxic Substances Control Act
Correct answer: C
Rationale: CERCLA, also known as Superfund,
provides federal authority to respond directly to
releases of hazardous substances and to compel
responsible parties to clean up contaminated sites.
2. The pH of normal, unpolluted rainwater is
approximately:
A) 4.0
,B) 5.6
C) 7.0
D) 8.2
Correct answer: B
Rationale: Carbon dioxide in the atmosphere
dissolves in rainwater to form carbonic acid,
resulting in a natural pH of about 5.6.
3. Which of the following is a primary pollutant that
directly contributes to the formation of
photochemical smog?
A) Carbon dioxide
B) Nitrogen oxides (NOx)
C) Methane
D) Chlorofluorocarbons
Correct answer: B
Rationale: Nitrogen oxides react with volatile organic
compounds in the presence of sunlight to form
ground-level ozone and photochemical smog.
4. The layer of the atmosphere that contains the
majority of Earth's weather phenomena is the:
A) Troposphere
,B) Stratosphere
C) Mesosphere
D) Thermosphere
Correct answer: A
Rationale: The troposphere extends from Earth's
surface to about 8-15 km and contains approximately
80% of atmospheric mass and most water vapor,
making it the site of virtually all weather.
5. Which hazardous waste characteristic is defined
as having a pH less than 2 or greater than 12.5?
A) Ignitability
B) Corrosivity
C) Reactivity
D) Toxicity
Correct answer: B
Rationale: Corrosive wastes are acidic (pH ≤2) or
alkaline (pH ≥12.5) and can destroy living tissue or
corrode metal containers.
6. The primary cause of eutrophication in freshwater
systems is excess:
A) Heavy metals
, B) Suspended solids
C) Nitrogen and phosphorus
D) Dissolved oxygen
Correct answer: C
Rationale: Excess nitrogen and phosphorus from
agricultural runoff, sewage, and detergents stimulate
algal blooms, leading to oxygen depletion and
ecosystem degradation.
7. Which US federal agency is primarily responsible
for protecting human health and the environment?
A) OSHA
B) EPA
C) FDA
D) DOI
Correct answer: B
Rationale: The Environmental Protection Agency
(EPA) was established in 1970 to enforce
environmental laws and regulate pollutants.
8. A confined aquifer is best described as:
A) An aquifer that is partially filled with water
