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Environmental and Health Issues and Recommendations  Less Hazardous:
When possible, reduce the use of products that contain high levels of chlorides, which could pose health risks to employees and the environment.
Highly corrosive materials should also be avoided as much as possible in order to prevent damage to application equipment and bridge structures.  Prevents Waste:
Non-chloride de-icers are less corrosive than water, helping to preserve structures, vehicles, and clothing.
See the Introduction for complete descriptions of these environmental and health issues.
BACKGROUND AND ENVIRONMENTAL AND HEALTH ISSUES
In the 1980s, environmental issues and the demand for better performance helped contribute to rapid changes in the de-icing industry. Many alternative de-icing products have been developed and are now available.
LAWS AND GUIDELINES
California
Statute
Chapter 318, Statutes of 1991 (Hauser, AB 220) required that the use of salt (sodium chloride) on state highways be reduced from the yearly average use from 1976 to 1988 (15,000 tons) or replaced with an environmentally safe de-icing method. See also California Streets and Highways Code section 95.6.
Policy
California Department of Transportation (Caltrans) Policy on Snow and Ice Removal from State Highways
"Snow removal and ice control shall be performed as necessary in order to facilitate the movement and safety of public traffic and shall be done in accordance with the best management practices outlined herein with particular emphasis given to environmentally sensitive areas." [1]
PERFORMANCE
Sidewalks, Walkways, and Bridge Decks
Potassium acetate and magnesium chloride are liquids that are reliable choices for areas such as sidewalks, walkways and bridge decks. On sidewalks and walkways, these products should be used with a fine sand to reduce slipperiness. On road and highway bridge decks, these liquids are applied with or without traction enhancing sand or other abrasives.
Although these products contain chlorides that may be damaging to plants in large quantities, they are less damaging than sodium chloride when applied properly. Ease of application is the main benefit of using these products.
Roads and Highways
Potassium acetate, magnesium chloride, and calcium magnesium acetate (CMA) are all acceptable substitutes for salt (sodium chloride). The two liquids, potassium acetate and magnesium chloride, can be applied directly to the roadway surface or used to pre-wet abrasives as they are applied from a truck. CMA is normally applied as a dry product, although it has been used successfully made into brine. The primary advantage of these types of products is their ability to act as a catalyst for dry sodium chloride. They tend to increase the efficiency of sodium chloride, thereby reducing the actual amount that needs to be applied. Salt brine has also been used successfully as a pre-wetting agent for abrasives and dry sodium chloride.
AVAILABILITY
Salt (sodium chloride) is the most readily available product. California buys solar evaporated salt as well as mined enhanced salt products. Liquid magnesium chloride is readily available as it is also used as a dust palliative. There has been little or no production of CMA for the past few years.
COST
Salt (sodium chloride) and similar products that are primarily chloride-based are initially cheaper to buy than alternative products. However, the long-term costs increase when infrastructure replacement of concrete and metal surfaces is taken into consideration.
Tips on Buying Deicing Products
Lower your de-icer budget by buying in large quantities if possible. For highways, stockpiling de-icers in well designed storage facilities can produce significant cost savings.
Use a statewide contract where available to secure cost savings. Using a contract produced by competitive bidding generally results in cost savings as well as providing protection from price increases due to market fluctuations.
SPECIFICATIONS
California
The Procurement Division of the Department of General Services develops and reviews specifications for statewide commodity standards and information technology. The current specification for de-icing salt is incorporated in statewide contract #1-04-68-10 Rev. F.
VENDORS
Statewide Contract
Several successful bidders are listed in the statewide contract (contract #1-04-68-10 Rev. F.). Note: This contract might not contain products with the environmental attributes that are discussed in this section.
Other Vendors
Products other than sodium chloride are purchased in smaller quantities from a variety of vendors not listed on the statewide contract.
SUCCESS STORY
See the Ice Control for Roads and Walkways section of the Environmentally Preferable Purchasing Guide published by the Solid Waste Management Coordinating Board of Minnesota.
RESOURCES AND WEBSITES
California Department of Transportation (Caltrans)
See the Caltrans Division of Maintenance, Road Information, Snow and Ice Control Program Web page.
Minnesota, Solid Waste Management Coordinating Board of (SWMCB)
The mission of the SWMCB is to increase the efficiency and environmental effectiveness of the region's solid waste management system. See the Ice Control for Roads and Walkways section of the SWMCB's Environmentally Preferable Purchasing Guide.
The Salt Institute
Fairfax Plaza, Alexandria, VA
(703) 549-4648
The Salt Institute is a source of information about salt and its more than 14,000 known uses. The Salt Institute is a non-profit association of salt producers (manufacturers).
United States Environmental Protection Agency (USEPA)
Washington, DC
(202) 272-0167
The USEPA's Planning Considerations for Roads, Highways and Bridges Web page discusses the storage and application of de-icers.
[1] California Department of Transportation. Division of Maintenance, Road Information, Snow and Ice Control Program Web page. Available at http://www.dot.ca.gov/hq/roadinfo/snwice.htm. Accessed on July 25, 2006.
Special Note: Portions of the Environmentally Preferable Purchasing Best Practices Manual were borrowed or adapted from the Environmentally Preferable Purchasing Guide published by the Solid Waste Management Coordinating Board of Minnesota.
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