Environmental Impact and Life-Cycle Analysis of Winter Roadway Abrasives
Recent research has challenged the effectiveness of roadway abrasives in certain
settings, but states throughout the nation still use roadway abrasives as part
of their winter maintenance programs. The use of these winter abrasives, such as sand or other products, can be costly to Department of Transportations (DOTs). At a typical
application rate of 1200 lbs per lane mile, product cost, post event sweeping,
waste management, and waste disposal can be significant cost considerations. Abrasives can create a post-storm waste stream that requires regular street sweeping to control the materials from entering drainage systems. Often, spent abrasives are contaminated through exposure to compounds found on road surfaces; therefore, the collected street sweepings must be sent to regulated landfills. In addition to routine maintenance and disposal costs, there are environmental costs associated with the use of roadway abrasives. Abrasives are contributing directly and indirectly to airborne particulate matter (PM-2.5). Indirect particulate matter has been shown to come from the actual road surfaces wearing as a result of the “sandpaper” effect. An Oregon Department of Transportation (DOT) study found that even after sweeping, 50-90% of applied sand remains in the environment. When these abrasives are transported through drainage systems, they can increase stormwater Best Management Practice (BMP) maintenance costs and potentially reduce BMP performance. An informal American Association of State Highway and Transportation Officials (AASHTO) query of state DOTs, indicated that some states do not use, or have eliminated the use, of abrasives in their winter maintenance programs. Given
the questionable effectiveness of winter abrasives and the costs for cleanup
and disposal, alternative deicers may be more cost effective. A life-cycle comparison of abrasives versus deicers could also consider the potential for Total Maximum Daily Load (TMDL) sediment credits to be generated through reductions in the application of such
materials and be used towards meeting sediment waste-load reductions. Additionally, reusing spent abrasive material in other roles such as alternative fill material may be more cost effective than landfill disposal.
The primary objective of this research is to
develop a report that includes an overview of the state of the practice
regarding winter abrasives, an evaluation of the life-cycle costs and
environmental impacts of abrasives versus alternative deicers as well as
abrasive disposal versus abrasive reuse, and recommendations regarding
application of abrasives versus their alternatives.
Some states have recognized the
limited effectiveness and environmental impacts of winter abrasives and have
subsequently reduced the use and cost of abrasives as a winter roadway
maintenance practice. However, many
states throughout the nation continue to employ winter abrasives and do not
have a sufficient decision tool with which to make practice choices. At procurement costs of $5-30 per ton, reducing,
eliminating, or reusing winter abrasives is a potentially sustainable and
economically profitable action for DOTs. Potential benefits enabled through the
proposed research include:
the basis for reducing or eliminating a winter maintenance practice that does
not exhibit favorable life-cycle-benefits;
the basis for alternative uses of spent abrasive material;
environmental impacts to surrounding water and air;
support to pursue TMDL sediment credits from the state TMDL authority or EPA.
quantity and characteristics of nationwide abrasive use;
previous research on the effectiveness of winter abrasives for traction
the life-cycle costs of abrasives versus alternative deicers, including:
to road surfaces; and
to water and air quality;
potential for spent abrasives to be used as alternative fill or other uses;
the feasibility of potential TMDL credits for eliminating abrasives; and
best practice recommendations to DOTs nationwide.
State DOTs are aware of the costs associated with winter abrasives, are learning about the effectiveness of these abrasives, and are concerned about the environmental impacts and therefore will champion this research.
Environmental and Winter Maintenance Divisions in State DOTs.
|Sponsoring Committee:||ADC60, Waste Management and Resource Efficiency in Transportation
|Research Period:||6 - 12 months|
|RNS Developer:||Andrew Graettinger and Ed Wallingford|
|Source Info:||Committee members|
|Index Terms:||Winter maintenance, Abrasives, Benefit cost analysis, Sand, Waste management, Drainage, Landfills, Environmental impacts, Life cycle costing, Deicers (Equipment), |
Maintenance and Preservation