AZ ROC CR-2 CONTRACTOR LICENSE STUDY
GUIDE VERIFIED ANSWERS &
EXPLANATIONS EXCAVATION & PAVING
EXAM PREP
This comprehensive practice exam provides verified multiple-
choice questions, answers, and detailed rationales tailored for
the Arizona CR-2 Excavating, Grading, and Oil Surfacing
contractor license. It covers critical exam topics including
OSHA trench safety standards, Southwest soil mechanics like
caliche management, and advanced asphalt paving
techniques. Optimized with clear formatting, this guide is the
ultimate preparation tool for achieving a passing score on the
2025/2026 Arizona ROC dual license examination.
1. What is the maximum allowable slope for an
excavation in Type A soil that is less than 20
feet deep?
A. 1:1
B. 1.5:1
C. 0.75:1
D. 0.5:1
Answer: C. 0.75:1
Rationale: According to OSHA subpart P, Type
A cohesive soils require a maximum allowable
slope of 3/4 to 1 (0.75:1) or an angle of 53
degrees from the horizontal if the trench is
under 20 feet deep.
,2. Which soil type cannot be classified as Type
A under any circumstances?
A. Clay
B. Silt clay
C. Sandy loam
D. Fissured soil
Answer: D. Fissured soil
Rationale: OSHA states that if a soil is
fissured, subject to vibration, or has been
previously disturbed, it cannot be classified as
Type A and must be downgraded.
3. At what depth does an excavation or trench
require a protective system such as shoring or
shielding?
A. 3 feet
B. 4 feet
C. 5 feet
D. 6 feet
Answer: C. 5 feet
Rationale: OSHA requires a protective system
for trenches 5 feet or deeper, unless the
excavation is made entirely in stable rock.
4. A stairway, ladder, or ramp must be located
in trench excavations so as to require no more
,than how many feet of lateral travel for
employees?
A. 15 feet
B. 25 feet
C. 50 feet
D. 100 feet
Answer: B. 25 feet
Rationale: OSHA standard 1926.651(c)(2)
requires a means of egress within 25 feet of
lateral travel for workers in trenches 4 feet or
deeper.
5. Excavated material (spoil piles) must be kept
at least how many feet from the edge of the
excavation?
A. 1 foot
B. 2 feet
C. 3 feet
D. 5 feet
Answer: B. 2 feet
Rationale: To prevent materials from falling
back into the trench, spoil piles and heavy
equipment must be kept a minimum of 2 feet
from the excavation edge.
, 6. What type of compactor is most effective for
compacting cohesive soils like heavy clay?
A. Smooth-drum roller
B. Vibratory plate compactor
C. Sheepsfoot roller
D. Pneumatic tire roller
Answer: C. Sheepsfoot roller
Rationale: Sheepsfoot rollers utilize kneading
action and high pressure to bond and compact
cohesive clay soils effectively from the bottom
up.
7. What does a Proctor test determine?
A. Soil moisture-density relationship
B. Liquid limit of the soil
C. Plasticity index
D. Shear strength of rock
Answer: A. Soil moisture-density relationship
Rationale: The Standard or Modified Proctor
test determines the optimum moisture content
at which a given soil type can achieve its
maximum dry density.
8. If a soil has a high Plasticity Index (PI), it is
predominantly composed of what material?
GUIDE VERIFIED ANSWERS &
EXPLANATIONS EXCAVATION & PAVING
EXAM PREP
This comprehensive practice exam provides verified multiple-
choice questions, answers, and detailed rationales tailored for
the Arizona CR-2 Excavating, Grading, and Oil Surfacing
contractor license. It covers critical exam topics including
OSHA trench safety standards, Southwest soil mechanics like
caliche management, and advanced asphalt paving
techniques. Optimized with clear formatting, this guide is the
ultimate preparation tool for achieving a passing score on the
2025/2026 Arizona ROC dual license examination.
1. What is the maximum allowable slope for an
excavation in Type A soil that is less than 20
feet deep?
A. 1:1
B. 1.5:1
C. 0.75:1
D. 0.5:1
Answer: C. 0.75:1
Rationale: According to OSHA subpart P, Type
A cohesive soils require a maximum allowable
slope of 3/4 to 1 (0.75:1) or an angle of 53
degrees from the horizontal if the trench is
under 20 feet deep.
,2. Which soil type cannot be classified as Type
A under any circumstances?
A. Clay
B. Silt clay
C. Sandy loam
D. Fissured soil
Answer: D. Fissured soil
Rationale: OSHA states that if a soil is
fissured, subject to vibration, or has been
previously disturbed, it cannot be classified as
Type A and must be downgraded.
3. At what depth does an excavation or trench
require a protective system such as shoring or
shielding?
A. 3 feet
B. 4 feet
C. 5 feet
D. 6 feet
Answer: C. 5 feet
Rationale: OSHA requires a protective system
for trenches 5 feet or deeper, unless the
excavation is made entirely in stable rock.
4. A stairway, ladder, or ramp must be located
in trench excavations so as to require no more
,than how many feet of lateral travel for
employees?
A. 15 feet
B. 25 feet
C. 50 feet
D. 100 feet
Answer: B. 25 feet
Rationale: OSHA standard 1926.651(c)(2)
requires a means of egress within 25 feet of
lateral travel for workers in trenches 4 feet or
deeper.
5. Excavated material (spoil piles) must be kept
at least how many feet from the edge of the
excavation?
A. 1 foot
B. 2 feet
C. 3 feet
D. 5 feet
Answer: B. 2 feet
Rationale: To prevent materials from falling
back into the trench, spoil piles and heavy
equipment must be kept a minimum of 2 feet
from the excavation edge.
, 6. What type of compactor is most effective for
compacting cohesive soils like heavy clay?
A. Smooth-drum roller
B. Vibratory plate compactor
C. Sheepsfoot roller
D. Pneumatic tire roller
Answer: C. Sheepsfoot roller
Rationale: Sheepsfoot rollers utilize kneading
action and high pressure to bond and compact
cohesive clay soils effectively from the bottom
up.
7. What does a Proctor test determine?
A. Soil moisture-density relationship
B. Liquid limit of the soil
C. Plasticity index
D. Shear strength of rock
Answer: A. Soil moisture-density relationship
Rationale: The Standard or Modified Proctor
test determines the optimum moisture content
at which a given soil type can achieve its
maximum dry density.
8. If a soil has a high Plasticity Index (PI), it is
predominantly composed of what material?
