The maximum concentration of a chemical compound which can result when it is dissolved in water.

The level of ground water or the upper surface of the zone of saturation of groundwater above an impermeable layer of soil or rock (through which water cannot move) as in an unconfined aquifer.

The maximum load of pollutants each discharger of waste is allowed to release into a particular waterway.

The treatment, storage, or disposal of liquid hazardous wastes in excavations, diked areas or ponds.

New Zealand-based artist Maurice Bennett converts ordinary slices of toast into art.

Two of the leading personal planner brands each have a loyal following, but which is better for the environment?

Tire buffings or nuggets of rubber from retreaded tires or used tires that have been ground up whole after removing their steel bands.

Paper waste that was not produced by, or has not passed through the end user or consumer. Preconsumer waste are paper materials that have been discarded during the product conversion process.

Pulp mills waste and discarded paper that contribute to land, air and water pollution. Prior to recycling, waste paper accounts for an average 35 percent in weight of municipal solid waste dumped in landfills in Canada and the US.

Mulch is any material applied over soil that is meant to protect or improve the soil area covered.

Natural materials such as fallen twigs, bark, flowers, leaves or applied plant materials such as grass clippings, hay and straw that go on top of soil surfaces and in the process help protect soil quality. Yard trash or clippings can be recycled as mulch.

Materials not derived from plants but are used as protective mulch over soil. Plastic, ground rubber, gravel, pebbles and crushed stone are examples of inorganic materials that can be used as protective soil cover.