10/08/2012 Council Packet - Laserfiche WebLink

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During the Storm sw Winter abrasives use has been documented as an air pollution concern. If you use a 50/50 salt/sand mix, you're generally either half right or half wrong. Using a salt/sand mix leads to overapplication of both materials. Sand that washes into a stream or lake may smother some small aquatic organisms. USING ABRASIVES Use winter sand and other abrasives when temperatures are too cold for deicing chemicals to be effective. But be aware that sand does not melt anything. It provides temporary traction, and only when it is on top. Sand also clogs sewers, ditches, and streams. As a result, avoid sand use as much as possible. A salt /sand mix is generally not recommended. Salt reduces the effectiveness of sand, and sand reduces the effectiveness of salt. However, a salt /sand mix may be helpful in limited situations such as a long freezing rain event where the salt is washed away quickly. A 25 to 50 percent sand /salt mix has been documented as effective in increasing friction by stick- ing the sand to the surface, like sandpaper. • Use abrasives in slow - moving traffic areas such as inter- sections and curves. • If your purpose is melting, use salt only. • Salt is ineffective in cold weather, so use sand or an alter- native chemical. • Sand is not cheap when you consider the handling, clean- up, and disposal costs. • Sweep up sand frequently, after each event if feasible. STANDARD PRACTICES • Know the pavement temperatures and trends to help you use the right application at the right time. Generally use less chemical when temperatures are rising and more when they are falling. • Don't apply dry salt (sodium chloride) at below 20° F pave- ment temperature. It will not melt fast enough to help and it will blow off the road into the ditch. • Below 20° F, switch to other tools like CaC12 and MgC12 at curves, hills, and intersections to obtain maximum melt- ing. If unavailable, use sand for traction. • Adjust your spinner speed to the lowest setting possible, except at intersections. • Drive at the slowest possible speed -17 to 25 mph— slight- ly higher if prewetting. • Don't let the traffic dictate your speed. Keep it slow to keep material on the road. • Apply deicers in the center of the road or high side of the curve. 10 • • •