Household hazardous waste (HHW) programs have become a very popular - and costly - component of many municipal solid waste (MSW) management systems. To justify the high expenditures, MSW managers must evaluate what citizens gain from the programs, which materials should be considered HHW, whether these materials pose a significant risk to human health or the environment and whether HHW can be properly managed in a Subtitle D landfill.
To help managers address these concerns, the Municipal Solid Waste Innovative Technology Evaluation (MITE) Program, a part of the U.S. Environmental Protection Agency (EPA), conducted a study to characterize HHW in Palm Beach County, Fla.
The objectives of the study were:
* To quantify the annual HHW tonnages disposed by residents, according to material type and on a net- and gross-weight basis;
* To quantify the annual HHW tonnages diverted through the Solid Waste Authority of Palm Beach County's HHW collection facility on a net- and gross-weight basis; and
* To compute HHW diversion rates by comparing the disposed and diverted tonnages.
According to the study, net weight consisted of material weight only, while gross weight included the material and the containers.
HHW disposal data were obtained by identifying and weighing HHW materials collected during 1993 and 1994. The HHW materials came from 117 residential MSW samples, each of which weighed between 200 and 300 pounds and were selected based on a statistical sampling of solid waste vehicles.
The study found that a total of 884 tons per year of HHW are generated in Palm Beach County (see pie chart). Of that, 695 tons per year are disposed and 189 tons per year are diverted (see table). These volumes compose approximately 0.1 percent of the 900,000 tons per year of residential MSW which are generated and disposed or recycled in the county.
Paints, automobile related materials, aerosols, cleansers and disinfectants, insecticides, batteries and adhesives represent the largest constituents of the county's generated HHW.
The combined HHW diversion rate was approximately 21 percent, according to the study. However, researchers were only able to make rough estimates, since private operations in the county also recycle HHW, particularly antifreeze, used motor oil and batteries. In addition, it is difficult to determine whether empty HHW containers have been disposed after residents have used all the materials or after dumping them down drains.
Some materials had high diversion rates and also represented a large portion of the total generated HHW. These included used motor oil and filters, paints and lead-acid batteries, totaling approximately 22 percent of the generated HHW. Increasing total diversion rates for the county hinges upon increased diversion of aerosols, cleansers and disinfectants, insecticides and adhesives, the study noted.
The situation varies for each community. Deciding to implement a HHW management program transcends mere numbers; political and social ramifications also must be assessed. However, characterizing a community's HHW is the first step toward making an informed decision - especially when re-sources are limited.
R.W. Beck, Seattle, conducted the study, with management oversight from the Solid Waste Association of North America (SWANA), Silver Spring, Md., ad funding from EPA. For more information, contact Dianne DeRoze, SWANA, P.O. Box 7219, Silver Spring, Md. 20907. (301) 585-2898.