Reuse program cuts quake disposal

Thanks to an innovative earthquake debris recycling program initiated by the Los Angeles County Sanitation Districts (LACSD), a large quantity of the materials from residences damaged by the january 1994 earthquake is being reused for beneficial purposes.

In a cooperative effort between LACSD and the Los Angeles Integrated Solid Waste Management Department, the county’s Calabasas Landfill accepted tons of debris from damaged or destroyed homes, walls, fireplaces and other structures. As disposal tonnage rose, sanitation engineers began to explore the potential for recycling some of the material to conserve resources and to limit landfilling.

After planning costs with the city, LACSD launched its pilot program on September 28 to collect, sort and reuse up to half of the 1,000 tons of debris then being trucked to the landfill for disposal daily; over 800 tons per day now are being sorted and processed.

Landfill weigh masters direct earthquake debris loads to the recycling point at the Calabasas working deck where the recycling contractor, Hayden Brothers of Sun Valley, Calif., conducts an initial hand-sort for large logs, stumps, metal items, large pieces of cardboard and greenwaste.

The remaining refuse is loaded into a processing line where dirt and other small items are mechanically separated and moved to designated locations in the recycled materials area for reuse. Remaining refuse drops onto a conveyor belt where it is further hand-sorted to collect wood and metal. Large blocks of concrete and bricks are crushed into reusable aggregate material.

Large logs and lumber are sold as firewood to firms that cut them into usable sizes. The branches and bushes composing the greenwaste are shredded and used as mulch and refuse cover at the landfill. Dirt recovered from the debris loads also is used as daily cover for refuse at the main landfill operating site, thus reducing the amount of dirt that must be obtained from other locations.

Scrap lumber and wood products are shredded and sold for use as fuel in power cogeneration plants in Southern California. Cardboard is sold to cardboard recyclers, and metal items are transported to metal salvagers.

Concrete aggregate is reused for roadbeds at the landfill, thus significantly reducing or eliminating the need to bring additional materials to the landfill to be used for that purpose.

As of the end of November, over 15,000 tons of earthquake debris had been recovered for recycling and other beneficial uses. More than 15 jobs were created to man the sorting stations and operate the equipment.

Although officials hoped to find a larger market for the items being recovered, the wide availability of wood and metal products from the earthquake’s destruction caused a glut in the market.

Nevertheless, officials, in cooperation with Los Angeles and the recycling contractor, plan to continue to refine the recycling process and increase efficiency as well as the total tonnage of materials recovered from the earthquake debris cleanup.