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3 Report from the Transportation Breakout Group1 T he transportation breakout group divided its discussions into three broad topics: technologies for reducing noise, guidance for purchasing, and future goals. In all three areas, said the group’s presenter, Nick Miller, the group thought about how to (1) instill an awareness of noise in NPS employees and park visitors, and (2) antici- pate problems before they arise. TECHNOLOGIES FOR REDUCING NOISE The vehicles used in national parks depend on the size and nature of the park and range from heavy- to light-duty, from snowplows to watercraft to aircraft. Fleets used solely for transporting visitors—buses, vans, or snowcoaches—may be owned by the park or by concessionaires. Others, such as trucks or patrol boats, are owned and operated by the parks and are used for park operations. Most parks also have off-road vehicles for maintenance and trail activities, and some authorize commercial vehicles for concessionaire use. Maintenance, the group decided, is one of the simplest and most effective approaches to control noise. And it has the added benefit of improving vehicle functionality, safety, and fuel efficiency. A parkwide inventory of vehicles would be a good beginning to a noise control program. Such an inventory could rank each piece of equipment by the total noise produced per unit of use (e.g., distance traveled or time employed). A loud vehicle may be less important if it is 1Transportation Breakout Group members were Jason Blough, Paul Donavan, Gregg Fleming, Kurt Fristrup, Nick Miller, and Kevin Percival. 22

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REPORT FROM THE TRANSPORTATION BREAKOUT GROUP 23 rarely used than a quiet one that is used more frequently. Theoretically, Miller said, the Park Service could use noise level as a way to prioritize which vehicles need the most maintenance and which should be retired and replaced by quieter vehicles. A national, park-specific inventory database could also support noise management. Weather and temperature are important considerations in managing noise from vehicles. Noise propagates differently depending on meteo- rological conditions, and understanding those effects when deploying vehicles is helpful in minimizing excessive noise. The group also discussed various technologies for quieter vehicles and more efficient engines, such as hybrid vehicles, electric vehicles, and engines that use alternative fuels or means of propulsion, such as hydro- gen helicopters with quieter rotors, aircraft with quieter propellers, or watercraft with four-stroke engines. Tracking these technologies is a good way to make sure that parks consider all options. GUIDANCE FOR PURCHASING When making purchases, noise standards are available from the Inter- national Organization for Standardization (ISO) and SAE International for almost all types of vehicles. Manufacturers may be reluctant to pro- vide exact numbers for vehicle noise but should be encouraged to do so. Partnerships with transit authorities and/or large private operators, such as FedEx and UPS, could be beneficial to the Park Service. Other government agencies, such as the US Army Tank Automotive Research Development and Engineering Center (TARDEC), can help with detec- tion specifications, vehicle technologies, and measurement procedures. Commercial purchasing partnerships may also be a strategy for the Park Service to consider. Leasing rather than purchasing vehicles could in some cases be beneficial, eliminating the need for maintenance and seasonal storage while allowing the lessee to set criteria for noise levels. Procurement specifications also could tie in with other initiatives such as NASA’s Buy-Quiet program or efforts to reduce fuel use and emis- sions of pollutants. Quiet tires, which have been investigated extensively in the Euro- pean Union, are another solution worth exploring. Putting limits on idling time, or adding smaller engines (e.g., auxiliary power units) for cli- mate control on vehicles such as tour buses, also could have an impact. When practical, transportation vehicles should not be left idling when not in use, although there are some cases (e.g., diesel engines in winter),

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24 PROTECTING NATIONAL PARK SOUNDSCAPES when idling is the preferred operating mode. Idling vehicles could be moved to sheltered locations to attenuate noise and improve vistas. Replacing backup alarms on vehicles (also discussed in Chapter 5) is another way to cut down on noise. New broadband alarms are available that can be adjusted to suit the situation. Beyond vehicles, mitigation possibilities in the parks include quiet pavements, which have been explored by the Federal Highway Adminis- tration (FHWA) in some states. Anti-icing overlays2 that absorb deicing liquid and release it when temperatures fall below freezing can reduce the need for snowplows. Charcoal spread on roadways and paths is a further measure to melt ice without the need for equipment. The group also suggested adding small berms at the side of roads; they would be low enough not to interfere visually but could help block tire-pavement noise. Moreover, reduced speed and the scheduling of transit vehicles could help reduce sound levels. FUTURE GOALS The group emphasized the importance of metrics to measure noise. Which metrics are used and how they are combined (or not) can be important in setting noise level goals for the parks. Data that have already been collected could be plotted in several useful ways and aug- mented as a noise control program takes shape. Goals for noise control achieved through such means as quiet zones or quiet times can be useful. Signs in parks could instruct motorcycles to “drive safely and quietly,” just as towns have signs prohibiting the use of engine brakes or railroad horns at roadway crossings. Goals need to reflect the location, time of day, season, and other factors. Goals also can be coordinated with FHWA efforts to quantify impacts in recreational areas along roads. Finally, the group touched on communications. Messages about noise can be conveyed not just through signs and brochures but through cell phones, texts, video, and many other means. A pilot program in selected parks could develop strategies for communicating with staff and the public. 2For more information, see