IIP a r tWATER AND WASTESAs part of the building design team, interior designers are responsible for making sure that the solid wastes generated during construction and building operation are handled, stored, and removed in a safe, efficient, and environmentally sound way. Whether we are designing an office cubicle to include a recycling basket or mak- ing sure that an old fireplace mantle is reused rather than discarded, we can have a significant impact on how the building affects the larger environment. Nature operates in closed cycles. One organisms waste is anothers food. Nothing is really wasted except a small amount of renewable energy from the sun. In- sects and microorganisms feed on the excrement and corpses of higher animals, releasing soil nutrients for plants. Dead vegetable matter is attacked, broken down, and used again. In agrarian societies, people, along with water, air, earthworms, and bacteria, convert animal and vegetable wastes into rich soil. Sun and rain on the soil encour- age plants to grow, feeding families and animals, and providing fuel for heating and cooking. Animals also provide food and clothing for people. Ashes from spent fuel and animal excrement return to replenish the soils nutrients. Today we discard many more materials: paper, plas- tics, glass, and metals; cinders, dust, dirt, and broken or worn-out machinery; kitchen garbage, and old clothes;and industrial by-products and radioactive and chemi- cal wastes from laboratories and industries. All of this averages out to about 45 kg (100 lb) of waste per per- son annually in the United States. Some of these mate- rials, such as food scraps and paper, are links in the bi- ological recycling chain. Some, such as metals and plastics, represent nonrenewable resources. Many waste substances contain useful energy, but separation and re- cycling of the mingled refuse is a Herculean task. Solid waste is the main source of land and soil pollution, next to the agricultural use of pesticides and fertilizers. Most cities burn and bury ashes, or bury the refuse itself in landfills. The organic components decompose, but glass, metals, and plastic remain.CONSTRUCTION WASTEIt is best to reuse, then to use up, and to recycle last of all. This applies to the construction and operation of the building. As interior designers, we can work with contractors to ensure that the materials removed during renovation and the waste generated by construction has a second life, possibly by including recycling require- ments in demolition specifications. Nationwide, demolition debris adds up to 165 mil-12C h a p t e rRecycling Solid Wastes60Recycling Solid Wastes61lion tons of waste per year. Some of it, especially as- phalt, concrete, bricks, and metal, is already recycled be- cause there is a market for it, but vast amount of shin- gles, carpet, wallboard, doors, windows, and other pieces of homes and offices find their way into landfills because the resale and recyclable market is poor. Be- tween 65 and 85 percent of construction debris ends up in landfills. Concrete and masonry can instead be crushed and used as aggregate for road building. Glass can be recycled into “glassphalt” road surface reflectors. Wood becomes mulch. Pulverized wood helps the com- posting of sludge at sewage treatment facilities. Drywall (gypsum wallboard) disposal can pose an environmental danger. Many landfills wont accept gyp- sum wallboard scrap because it produces toxic hydro- gen sulfide gas when buried. However, it can be recy- cled, with up to 85 percent of the material reused for new gypsum wallboard. Unpainted drywall can also be composted, replacing lime in the soil. Manufacturers currently sponsor programs that take back used carpet, which is ground up for attic insula- tion or recycled into new carpet. Plate glass becomes fiberglass insulation. Acoustic tiles can be recycled into new acoustic tiles. Many new building materials can be made from recycled materials. Scrap metal containing iron is used to make reinforcing bars for concrete. Newsprint is chopped into small pieces to become cellulose insula- tion. Recycled plastic products include fence posts, speed bumps, deck planking, and park benches. Incin- erator ash is used in nonstructural concrete. Even yogurt containers with aluminum seal scraps can become terrazzo-like floors. Look for opportunities to use recy- cled materials in your designs. Demolition by hand salvage produces useful building components and even some architectural gems. The dismantling of a building generates reusable roof boards, framing lumber, and tongue-and-groove wood flooring. Doors, windows, bathroom fixtures, plywood, siding, and bricks can all be reused. Furniture, equipment, and appliances can be reused. When check- ing out a building for a renovation project, consider which elements can be reused in your design or salvaged for another project. Some contractors sort excess or used building ma- terial into bins right at the