ENVIRONMENTAL NOISE

Environmental or “Community” Noise is a major concern in all areas, as residential development expands within cities and rural areas. Conflicts continually arise between residents and those who would produce noise. 

Major “culprits” are “boom cars,” construction, motor race tracks, industrial and commercial establishments, aircraft, mining operations, and road traffic – but a surprisingly large number of complaints come from relatively simple problems like noisy air conditioners and pool pumps, barking dogs or footfalls in multi-level dwellings that can be easily solved.

ESA specializes in environmental noise remediation, including the development of noise ordinances and training of enforcement personnel. We are active with the Noise Pollution Clearing House (www.nonoise.org) and serve as the technical advisor to Noise Free America, a national group dedicated to the reduction of noise (www.noisefree.org).   

Case # 1

In an NFA case, a resident in central Ohio was desperate to stop the noise from a nearby mine that had just started although the mine had been in operation for years. A horn was going off every 8-10 minutes throughout the night. Subsequent investigation with the corporate safety director revealed that the horn was used to warn employees in a tunnel that a conveyor was about to start. The horn used to be in the tunnel – but it was moved outside because it was too loud!

Our recommendation was to replace the horn with flashing strobes inside the tunnel. I would imagine that the safety director’s recommendation was to replace the ‘boneheads’ who originally selected the horn and then moved it outside instead of replacing it.

Case # 2

A noise issue at a paper processing facility in Neenah, Wisconsin had gone into litigation before we were called to assist. Residents were complaining about unknown noise from industrial ventilation equipment at the facility that was exceeding the ordinance limits at the property line.

Our first step was to interview the complainants to determine what they were hearing. This is a very important in these types of issues. The answers are often surprising.

On a very cold day in February, I found myself on top of the facility roof taking sound measurements and recordings of the noise from various blower exhaust and intake vents. We met again with the residents, played the recordings, zeroed in on what was causing the noise, and made recommendations for silencers that solved the problem.

This was similar to another case in northern Ohio, where a large manufacturing facility was producing noise distinguishable over a mile away – but not on the ground next to the building. A single $1500 silencer resolved what many thought would be a major undertaking.

Rooftop vents at Wisconsin plant. Many were “measured,” but only one needed a silencer

View from the roof of an Ohio facility at a blower vent.

Reflective surfaces like that shown at the right played a role in increasing

sound transmission to residences well beyond the railroad tracks 

Case # 3

Noise need not be “excessive” to be annoying. In an interesting case, an elderly resident of northern New York was being awakened regularly by the “siren-like” sound produced by a mine ventilation fan several miles away. Although the sound measured only 29dBA at his property line, we found through our interview that he had been a volunteer fireman for many years, and the fan was producing the same tone that he had been conditioned to respond to.

He paid for a new fan blade assembly with more blades. The new fan moved more air – and the sound was reduced and shifted to a higher frequency.

This is a good example of people working together, instead of going to court, to try to resolve noise issues. Our role as a mediator often produces excellent results. We have found on numerous occasions that the cost of remediation is far less than the costs of litigation.

Case # 4

Recreational facilities are a common source of conflict with regard to noise. We work regularly with not only citizen groups and attorneys, but those designing race tracks, shooting ranges, nightclubs, etc. - or defending themselves against noise complaints.

In these issues, we find that both sides may have valid positions. Our job is to bring logic to a discussion that may be dominated by emotion. All parties need to know what can be done to reduce noise – and what cannot. We are constantly dealing with “hidden agendas” – people complaining about noise when other issues are dominating their thoughts.

In many instances of development, we perform the noise portion of the environmental impact study for the New York State Department of Environmental Conservation. In this case, working for a developer of a motocross facility in the Mohawk Valley, we recorded and analyzed the sound data from nearby tracks and, working with topographical maps, photos, and information supplied by the American Motorcyclist Association, developed plans for a track layout and sound barriers that would satisfy virtually all demands.

The small valley at the tree line in the distance was the recommended site of the motocross facility, with the natural slope of the land and the trees forming a noise barrier between the facility and residential areas

 Case # 5

A few years ago, we received a call to help solve a unique problem in Geneva, NY where vibration from a foundry was suspected of cracking windows in homes several blocks away. Vibration tests showed a “signature” that was traced to a “shakeout system” at the foundry that was “in resonance” with the soil at this end of Seneca Lake. Speeding up the shakeout changed this “forcing frequency,” and allowed the displacement (amplitude) of the vibration to be reduced without affecting performance.