A growing number of states and landfills are recognizing the benefits of using automotive shredder residue (ASR) as landfill daily cover material, according to a nationwide survey conducted by the Recycling Research Foundation (RRF), Washington, D.C.
ASR is defined in the survey as the material left over after automobiles are shredded. It contains a large variety of non-metallics, including fabric, dirt, foam rubber, wire, plastic, wood, rubber and paper.
Of the 47 states where ASR was available, 85 percent have approved its use as daily cover material in landfills or would consider approving ASR as daily cover.
RRF sent questionnaires to 130 shredder operators who are members of the Institute of Scrap Recycling Industries (ISRI), Washington, D.C., asking about state regulations, problems with cover material and other issues. Twenty-five operators responded, according to Mary Ann Baviello, senior risk analyst for Environmental Liability Management Inc., Holicong, Pa., who co-authored the nationwide study.
The organization then called solid waste departments in 25 states that met certain criteria, including those that:
* Had ASR regulations;
* Approved the use of specified solid waste as alternative daily cover (ADC) material, such as tires;
* Had five or more shredder operators in the state; and
* Responded to the original questionnaire.
"It was a good cross section of the country, but we did have to make some generalizations for the whole country," Baviello says, adding that researchers asked the departments about ASR policies, regulations and practices. RRF also queried some landfill operators across the country that use ASR as landfill covers.
Twenty-two other states also received brief phone calls. Oregon, Indiana and Georgia asked not to be contacted, she says.
Of those 47 states contacted, 40 said they have approved or would approve ASR for use as an ADC.
Many states had different experiences with ASR, according to the survey. Wisconsin, for example, conditionally mandates the use of ASR as an alternative daily cover, while Louisiana specifically excludes ASR from its definition of solid waste.
Massachusetts requires a shredder operator to demonstrate that all other management options are technically or economically not feasible (including beneficial use) before ASR can be disposed as waste in a landfill. In Florida, when ASR is used as cover material and is handled properly, it is considered to be recycling.
The survey also found:
* ASR is ideally suited for landfill applications, especially considering the Resource Conservation and Recovery Act (RCRA) mandate to recover/reuse materials and to conserve resources.
* ASR is non-hazardous when sources of lead, cadmium and PCBs are minimized in the feedstock.
* ASR has properties that are compatible with RCRA criteria for acceptable sanitary landfill daily cover materials.
* Landfill operators currently using ASR are pleased with the way it performs as cover material, and several noted that the relatively high water absorbency made ASR easier to handle in wet conditions compared to soil.
States that have not approved ASR for beneficial use often do so because of misperceptions of ASR's characteristics and the lack of recognition of the overall economic, social and regulatory benefits from beneficial use of ASR in landfills, according to the survey.