Although only a small percentage of the solid waste tonnage, household hazardous waste (HHW) represents the majority of toxic components in the solid waste stream.

More than 1 million tons of HHW are disposed of annually across the country - an amount which demands some degree of management. Formerly, the only HHW programs were special collection events typically held one day each year at non-permanent sites. In recent years, however, an increasing number of permanent collection facilities have been established.

For example, Brown County, Wis., recently created a permanent indoor HHW collection and processing facility - the first in the state.

Since 1981, the county has hosted annual "clean sweep" events, collecting an average of 20,100 pounds of HHW per year, according to Dean Haen, a spokesperson for the Brown County Solid Waste Department. But that is only a fraction of the hazardous waste that actually is disposed.

In 1993, the waste department, with the assistance of the Green Bay Metropolitan Sewerage District, studied alternatives to the annual collection event that would increase citizen participation.

This would reduce the amount of landfilled HHW, thus lowering costs by reducing leachate toxicity and groundwater contamination. Also, reducing the amount of toxic chemicals entering the sewer system would improve the quality of the effluent discharged to the Fox River and safety conditions at the Green Bay treatment plant.

The alternatives considered included: multiple one-day collection events, a permanent collection facility and, a permanent collection facility with integrated satellite and/or mobile collection facilities.

In February 1996, the Brown County Solid Waste Board approved a $434,000 plan to build a permanent disposal facility adjacent to the existing Materials Recycling Facility in the village of Ashwaubenon. The site is operated year-round and will accept HHW two days a week during its first year.

The facility's designers, Robert E. Lee & Associates, Greenbay, Wis., toured several HHW facilities for ideas before construction. As a result, the 4,320-square-foot facility was completed at a lower cost than other facilities of similar size despite having to correct subgrade instability.

One design feature that lowered cost and improved safety was the elimination of the sumps normally constructed for spill containment. Instead, the floor was sloped to contain spills on the surface, making them immediately apparent and easier to clean.

The segregated flammable materials storage building also contributed to cost savings and improved safety. This 890-square-foot structure, built for handling and storing class lA and lB flammable liquids, was a result of a discussion between the engineers and the National Fire Protection Agency. By segregating this storage area, the need for deflagration (explosion) venting and a sprinkler system for fire suppression was eliminated.

And, in a move to promote efficient material flow, engineers designed the product exchange room, where usable products are given back to the public, adjacent to the receiving area.

The year-round permanent facility has reduced unit costs in other ways, too:

* permanent, trained staff eliminates the need for contracted services;

* set-up and take-down time is not necessary, as with the one-day events; and

* a permanent site provides a better opportunity for ongoing citizen education.

In less than two months of operation (When was this facility built?), the quantities received at the site already have surpassed the annual clean sweep totals. With storage capacity, on-site waste reduction practices can be used, including acid and base neutralization, material bulking and aerosol can decanting. The product exchange program also will reduce disposal costs, possibly by as much as 60 percent, according to Haen.

However, because HHW is exempt from hazwaste disposal regs, the program relies on voluntary participation. Education will be key to the program's success, since many people do not know of the potential danger in their household products or even that this facility exists. (Briefly describe the educational efforts.)

But the ultimate goal of education is to permanently change people's purchasing and disposal habits. Fortunately, over the past few years, the public has strongly supported these types of programs.