Describes the degree, level, or significance of an effect as no effect, negligible, minor, moderate, or significant.
No effect: No discernible effect.
Negligible: Effect is at the lowest level of detection and causes very little or no disturbance or improvement.
Minor: Effect that is slight but detectable, with some perceptible effects of disturbance or improvement.
Moderate: Effect is readily apparent and has measurable effects of disturbance or improvement.
Significant: Effect is readily apparent and has measurable effects of disturbance or improvement that are of local, regional, or global importance; or sets a precedent for future project undertakings by Federal agencies.