ICC Soils Certification Test Question and
Answer 2026 | Updated Notes with Detailed
Explanations | A+ Verified
• clay. CORRECT ANSWER: soil passing No. 200 (75 micron) US
standard sieve
fine-grained soil
plasticity index =/> 4
plot of PI vs LL falls on or above the "A" line
• gravel. CORRECT ANSWER: particles of rock that will pass a 3" (75
mm) sieve and be retaoned on a Nom 4 (4.65 mm) US standard sieve
• coarse gravel. CORRECT ANSWER: passes 3" (75 mm) sieve and
retained on the 3/4" (19 mm) sieve
• fine gravel. CORRECT ANSWER: passes 3/4" (19 mm) sieve and
retained on No. 4 (4.75 mm) sieve
• organic clay. CORRECT ANSWER: clay with sufficient organic
content to influence the soil properties
, LL value after oven drying is <75% of its LL before oven drying
• organic silt. CORRECT ANSWER: silt with sufficient organic content
to influence the soil properties
LL value after oven drying is <75% of its LL value before oven drying
• peat. CORRECT ANSWER: soil composed of vegetable tissue in
various stages of decomposition usually with an organic odor, a dark
brown to black color, spongy consistency, and a texture ranging from
fibrous to amorphous
• sand. CORRECT ANSWER: particles of rock that pass a No. 4 (4.75
mm) sieve and be retaoned on a No. 200 (75 micron) US standard sieve
• coarse sand. CORRECT ANSWER: passes No. 4 (4.75 mm) sieve and
retained on No. 10 (2 mm) sieve
• medium sand. CORRECT ANSWER: passes No. 10 (2 mm) sieve and
retained on No. 40 (425 micron) sieve
• fine sand. CORRECT ANSWER: passes No. 40 (425 micron) sieve
and retained on No. 200 (75 micron) sieve
• silt. CORRECT ANSWER: soil passing No. 200 (75 micron) US
standard sieve
Answer 2026 | Updated Notes with Detailed
Explanations | A+ Verified
• clay. CORRECT ANSWER: soil passing No. 200 (75 micron) US
standard sieve
fine-grained soil
plasticity index =/> 4
plot of PI vs LL falls on or above the "A" line
• gravel. CORRECT ANSWER: particles of rock that will pass a 3" (75
mm) sieve and be retaoned on a Nom 4 (4.65 mm) US standard sieve
• coarse gravel. CORRECT ANSWER: passes 3" (75 mm) sieve and
retained on the 3/4" (19 mm) sieve
• fine gravel. CORRECT ANSWER: passes 3/4" (19 mm) sieve and
retained on No. 4 (4.75 mm) sieve
• organic clay. CORRECT ANSWER: clay with sufficient organic
content to influence the soil properties
, LL value after oven drying is <75% of its LL before oven drying
• organic silt. CORRECT ANSWER: silt with sufficient organic content
to influence the soil properties
LL value after oven drying is <75% of its LL value before oven drying
• peat. CORRECT ANSWER: soil composed of vegetable tissue in
various stages of decomposition usually with an organic odor, a dark
brown to black color, spongy consistency, and a texture ranging from
fibrous to amorphous
• sand. CORRECT ANSWER: particles of rock that pass a No. 4 (4.75
mm) sieve and be retaoned on a No. 200 (75 micron) US standard sieve
• coarse sand. CORRECT ANSWER: passes No. 4 (4.75 mm) sieve and
retained on No. 10 (2 mm) sieve
• medium sand. CORRECT ANSWER: passes No. 10 (2 mm) sieve and
retained on No. 40 (425 micron) sieve
• fine sand. CORRECT ANSWER: passes No. 40 (425 micron) sieve
and retained on No. 200 (75 micron) sieve
• silt. CORRECT ANSWER: soil passing No. 200 (75 micron) US
standard sieve
