Glossary

Glossary

LAND FARMING:

Method of removing petroleum compounds from soils. Contaminated soils are removed from the ground, spread over a given area, and periodically, tilled to speed up the release of VOC's and breakdown of the contaminants. (See AERATION.)

LAND RECYCLING:

The reuse of abandoned or underused properties, often environmentally distressed, for redevelopment. Land recycling is an inherently sustainable idea, based on the same common sense logic as materials recycling. Like other natural resources, land represents a shared investment that should be reused and recycled, rather than consumed and abandoned after use.

LANDFILL:

Landfills are principally disposal sites for municipal refuse and some industrial wastes. Some landfill may accept petroleum-contaminated wastes depending upon their permits.

LD50:

The dosage of a toxic substance required to kill one half of the organisms under study in a given period of time. 

LEACHATE:

Any fluid, formed by the drainage of liquids from waste or by the percolation of liquid through waste. It includes any constituents extracted from the waste and dissolved or suspended in the fluid. Often refers to liquid leaking from landfills which usually contains contaminates.

LEAD AGENCY:

A public agency that has the principal responsibility for ordering and overseeing site investigation and cleanup.

LEAD:

A heavy metal that has been used in the manufacture of gasoline, paints, and other substances. (See HEAVY METAL.)

LIGHT NONAQUEOUS PHASE LIQUID (LNAPL):

 One of a group of organic substances that are relatively insoluble in water and are less dense than water. LNAPLs, such as oil, tend to spread across the surface of the water table and form a layer on top of the water table.

LINER:

A continuous layer of natural or artificial materials or a continuous membrane of artificial material installed beneath or on the sides of a waste management unit, which acts as a barrier to vertical or lateral fluid movement. 

LITHOLOGY:

Gross physical character of a rock or rock types in a stratigraphic section.

LOAN-TO-VALUE RATIO (LTV):

An expression of the safety of the principal of the loan based on the value of its collateral. Typically, it is the amount yielded by dividing the loan amount by the project value. A borrower would typically want a high LTV. The lower the LTV, the lower the risk to the lender, for in the case of default, there would exist a greater gap between the outstanding loan balance and the project value. The LTV will normally decline over the life of the loan as principal payments reduce the loan amount and inflation enhances the property’s value.

LOAN-TO-VALUE RATIO (LTV):

An expression of the safety of the principal of the loan based on the value of its collateral. Typically, it is the amount yielded by dividing the loan amount by the project value. A borrower would typically want a high LTV. The lower the LTV, the lower the risk to the lender, for in the case of default, there would exist a greater gap between the outstanding loan balance and the project value. The LTV will normally decline over the life of the loan as principal payments reduce the loan amount and inflation enhances the property’s value.

LOCAL AGENCY:

The department, office, or other agency of county or city designated to have oversight authority for directing the remediation of an unauthorized release.

LONG-TERM MONITORING:

Typically is performed on a site to verify that contaminants pose no risk to human health or the environment and that natural processes are reducing contaminant levels and risk as predicted. 

LOWER EXPLOSIVE LIMIT (LEL):

The concentration of a gas below which the concentration of vapors is insufficient to support an explosion. LEL's for most organics are generally 1 to 5 percent by volume.

LUFT MANUAL:

A field manual to provide practical guidance to regulatory agencies, consultants, and RP's in investigating and remediating their sites.

LUST:

Leaking underground storage tank. USTs for petroleum and hazardous substances are regulated under the 1984 amendments to RCRA.