Glossary

Southern Sonoma County
Resource Conservation District

We hope that this glossary will help you to define a term.
Please select a letter from the table below.

F-G-H-I-J P-Q-R-S T-U-V-W-X-Y-Z

Fault. A fracture in the earth's crust forming a boundary between rock masses that have shifted. An active fault is a fault that has moved recently and which is likely to again. An inactive fault is a fault which shows no evidence of movement in recent geologic time and little potential for movement.

Groundwater. Water under the earth's surface, often confined to aquifers capable of supplying wells and springs.

Groundwater Recharge. The natural process of infiltration and percolation of rainwater from land areas or streams through permeable soils into water-holding rocks that provide underground storage (i.e. aquifers).

Habitat. The natural environment of a plant or animal.

Hazardous Material. A material or form of energy that could cause injury or illness to persons, livestock, or the natural environment.

Hazardous Waste. Waste which requires special handling to avoid illness or injury to persons or damage to property. Includes, but is not limited to, inorganic mineral acids of sulfur, fluorine, chlorine, nitrogen, chromium, phosphorous, selenium and arsenic and their common salts; lead, nickel, and mercury and their inorganic salts or metallo-organic derivatives; coal, tar acids such as phenol and cresols and their salts; and all radioactive materials.

Hydrocarbons (HC). Gases emitted from incomplete combustion of gasoline and from evaporation of petroleum fuels, representing unburned and wasted fuel.

Impervious Surface. Any material which reduces or prevents absorption of water into land.

Infiltration. The introduction of underground water, such as groundwater, into wastewater collection systems. Infiltration results in increased wastewater flow levels.

Infrastructure. Permanent utility installations, including roads, water supply lines, sewage collection pipes, and power and communications lines.

©2004 Southern Sonoma County Resource Conservation District