Landfill – Area where waste is dumped and eventually covered with dirt and topsoil.

Lead – Harmful to the environment used in a lot of paints. It's also toxic to humans.

LED / LED Lighting - LEDs, or light-emitting diodes, produce more light per watt than incandescent bulbs. LED bulbs last more than 15 times longer, use less energy and are better for the environment.

LEED™ (Leadership in Energy and Environmental Design) - A series of building rating products developed by the U.S. Green Building Council (USGBC) to provide a standard for what constitutes a “green building” or “high performance” building.

The various LEED products are used as design guidelines and third-party certification tools, aiming to improve occupant well-being, environmental performance and economic returns of buildings used to establish and innovative practices, standards and technologies.

The collection of LEED products includes LEED New Construction (NC) for newly constructed buildings, LEED Commercial Interiors (CI) for tenant build-outs, LEED Existing Buildings (EB) for existing building operations and for re-certification of already certified buildings, and LEED Core and Shell (CS). An effort is also underway to develop LEED for Homes.

LEED NC - LEED for New Construction and Major Renovations is designed to guide and distinguish high-performance commercial and institutional projects.

LEED EB - LEED for Existing Buildings: Operations & Maintenance provides a benchmark for building owners and operators to measure operations, improvements and maintenance.

LEED CI - LEED for Commercial Interiors is a benchmark for the tenant improvement market that gives the power to make sustainable choices to tenants and designers.

LEED CS - LEED for Core & Shell aids designers, builders, developers and new building owners in implementing sustainable design for new core and shell construction.

LEED for Homes - Promotes the design and construction of high-performance green homes.

LEED for Schools - Recognizes the unique nature of the design and construction of
K-12 schools and addresses the specific needs of school spaces.

LEED for Retail - Recognizes the unique nature of retail design and construction projects and addresses the specific needs of retail spaces.

LEED for Healthcare - Promotes sustainable planning, design and construction for high-performance healthcare facilities.

LEED for Neighborhood Development - Integrates the principles of smart growth, urbanism and green building into the first national program for neighborhood design.

Locally Sourced – The philosophy of buying food, and/or items, that were produced in, or near, the region of the consumer. By doing this, one can theoretically reduce emissions and waste by eliminating unnecessary transport of goods.

Life cycle assessment – Methodology developed to assess a product's full environmental costs, from raw material to final disposal.

Light pollution – Environmental pollution consisting of the excess of harmful or annoying light.

Low-emission vehicles – Cars etc which emit little pollution compared to conventional engines.