How is frozen soil characterized?

• A. Soil that is wet and muddy
• B. Ground that is impenetrable due to frozen moisture, not easily penetrated by a metal object, and has a temperature below 32°F
• C. Soil that is thawing
• D. Soil that is dry and loose

Answer: (B)

Frozen soil is soil where the moisture is ice and the ground is at a temperature at or below 32°F, making it hard and resistant to penetration. Because the water in the soil is frozen, the surface and subsurface become stiff, so a metal object or probe can’t easily push into it. This combination of frozen moisture and subfreezing temperature is what characterizes frozen soil. The other descriptions describe unfrozen conditions—wet and muddy, thawing, or dry and loose—none of which match the frozen state.