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12.0 Glossary

Trophic: Of or involving the feeding habits or food relationship of different organisms in a
food chain.

Trustee Agency: A State agency having jurisdiction by law over natural resources affected
by a project which are held in trust for the people of the state of California. Trustee agencies
include the California Department of Fish and Wildlife, State Lands Commission, the State
Department of Parks and Recreation, and the University of California (with regard to sites
within the Natural Land and Water Reserves System) (State CEQA Guidelines, Section
15386).

Tsunami: A sea wave produced by large-scale, short-duration disturbance of the ocean floor
such as from subsidence, an earthquake, or a volcanic eruption.

Tuffaceous: Rock formed as a deposit from springs or streams.

Tuff beds: Clusters of consolidated rocks of any size ejected from a volcano. Tuff is a general
term for all consolidated pyroclastic rocks, meaning rocks formed of unreworked solid
material of any size ejected from a volcano.

Turbidity: The cloudiness or haziness of a fluid caused by individual particles (suspended
solids) that are generally invisible to the naked eye. The measurement of turbidity is a key
test of water quality.

Turn Lane: A lane devoted to vehicles making a turning movement to go in a different
direction. Turn lanes are necessary to ensure the free-flow of traffic in the through lanes by
providing a separate area/lane for turning traffic to slow down and complete the turning
maneuver without impeding the through traffic.

Undercutting: Excavation at the base of an unstable slope to allow for stabilization
measures.

Underground Storage Tank (UST): Refers to tanks used to store gasoline underground.

Unifacial: Flaked in such a way as to produce a cutting edge that is sharp on one side only.

Uniform Building Code (UBC): A national, standard building code that sets forth minimum
standards for construction, published by the International Conference of Building Officials
(ICBO).

Uniform Housing Code (UHC): State housing regulations governing the condition of
habitable structures with regard to health and safety standards, and which provide for the
conservation and rehabilitation of housing in accordance with the Uniform Building Code
(UBC).

United States Environmental Protection Agency (USEPA): The federal agency with
primary responsibility setting of policy and guidelines and carrying out legal mandates for
the protection of natural interests in environmental resources, including the Clean Water

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Draft EIR