The King County Fleet Administration Division has been evaluating environmentally preferable systems for washing parts during vehicle and equipment maintenance. The Division, along with the Solid Waste Division's Cedar Hills Landfill, recently purchased eight aqueous part washers that do not use hazardous solvents. Metro Transit has also purchased one unit, for evaluation. These units not only use water instead of petrochemical solvents, they use non-hazardous bioremediation (using microbes) to clean greasy parts. The by-products of this system are non-hazardous: water and carbon dioxide.

According to King County Fleet's Equipment Supervisor, Bob Toppen, the product works great and is meeting all of their criteria for health, safety, environment and effectiveness.

Although petrochemical solvents are effective for cleaning, they create a hazardous waste and raise significant environmental and human health concerns. Federal, state and local initiatives concerning our air quality might soon restrict or ban solvent washers in the Puget Sound area, as they have in California. The Washington State Department of Ecology has issued a statement that says "Regulatory and economic pressures stemming from the environmental and health effects of solvents have lead to a search for less hazardous substitutes." Aqueous cleaners are water-based solutions that, unlike petroleum-based solvents, are typically nonflammable and contain little or no Volatile Organic Compounds (VOCs), which damage the atmosphere. In the systems these County agencies are using, the microbial bioremediation rapidly breaks down the organic compounds, through the use of enzymes, bacteria, or fungi. The microbes attack and eat oil and grease particles. They are safe and effective. Although they clean differently, aqueous cleaners perform as well as solvents.

King County's Equipment Supervisor points to a number of areas in which this system is preferable to the old solvent systems. The new system:

The bioremediating parts washers worked so well in tests, that both Fleet and Cedar Hills expanded their use system-wide. It was very good at dissolving grease and oil, but did take longer for heavy gear oil such as 90-weight transmission oil. Additional comments by Fleet staff include that the unit is portable, works 24 hours a day, there are no noxious odors, and the solution never needs to be treated or disposed of, just replenished.

Fact Sheet:

Environmental Protection Agency's Best Environmental Practices for Fleet Maintenance - aqueous parts cleaning

 

King County vendor:

EnviCARE USA

Model: SmartWasher

Contact: Catherine Edwards, President/CEO

Phone: (253)333-0403