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21 CHAPTER FOUR ENVIRONMENTAL RESPONSIBILITY Some traditional winter operation strategies are no longer without ferrocyanide salts are `toxic' as defined in Section 64 practical owing to environmental constraints. Sixteen of the of the Canadian Environmental Protection Act, 1999" and responding agencies reported investigating environmental mandated salt management practices ("Assessment Report-- impacts related to winter operation activities. Most agencies Road Salts" 2003). This has driven substantial efforts in are making efforts to minimize those impacts through more developing such management practices. restrictive use of the impacting strategies, clean-up practices after an individual storm or the winter season concludes, and The runoff pollution problem occurs at both the roadway, better containment of materials. where chemicals are applied, and in association with storage of materials, primarily road salt stockpiles. In general, adop- A practice that contributes to adverse environmental tion of salt management practices and increased attention to impacts is the use of deicing abrasives, including sand. Under associated environmental impacts of chemical treatments are the action of traffic much of the sand applied to the road- increasingly important. Many agencies have made modifica- way is ground into very fine particles and then, as it dries, tions to their road salt storage practices by covering stock- it becomes airborne. This can result in PM-10 air quality piles and capturing runoff. Stockpiles are being protected nonattainments for many areas. In addition, these particles through a variety of methods including construction of struc- can generate silting issues associated with nearby bodies of tures designed specifically to house and protect road salt and water. Some agencies have responded to these issues by lim- the use of spray-on stockpile applications that waterproof the iting the use of sand and by recovering it, and, like Edmonton, stockpile itself. occasionally recycling it. Oregon makes a concerted effort to recover abrasives in stream-sensitive areas at the end of each An example is the PNSA's earlier-mentioned anti-icing winter season. Nevada sweeps where they experience non- chemical specifications that emphasize safety, environmen- attainment problems. tal preservation, infrastructure protection, cost-effectiveness, and performance. In Montana, response to winter storms does One of the winter operation activities that can affect the not begin until maintenance managers are certain that snow environment is the use of road salt and other chemicals. As or ice will occur. This approach was implemented in response shown in Table 4, many states apply chemicals to the road- to public pressure to use road chemicals conservatively out way to prevent bonding between ice or snow and the pave- of concern for the environment and for their vehicles. In Ore- ment surface. These chemicals can have significant impacts gon, where the public has also emphasized the concern for by polluting storm water runoff and infiltrating other bodies these impacts, ODOT has implemented best management of water. In November 2001, Environment Canada concluded practices that address all aspects of routine road mainte- that "road salts that contain inorganic chloride salts with or nance, including winter operation activities.