Original Date: 08/08/1994
Revision Date: 01/18/2007

Since 1984, CSTA has instituted several operational initiatives to reduce environmental noise impact to surrounding communities and to better balance CSTA's mission with community concerns. Before that time, predicting or assessing noise propagation was not conducted because of the tedious mathematical computations required and the lack of adequate weather data. A primitive warning system with a limited number of sensors around the Proving Ground proved inadequate.

A computerized modeling program developed to predict noise propagation in 1988 by the University of Dayton and the Atmospheric Sciences Laboratory was installed at CSTA. The program accounted for meteorological factors that affected noise propagation such as air density, temperature inversions, and wind speed and direction. The meteorological measurements needed to predict noise propagation included surface wind and temperature, and wind and temperature aloft which CSTA has the capability to measure with sensitive ground and airborne sensors. The Noise Model used this meteorological data with the charge weight and firing site to produce a decibel (dB) contour level map for the noise distribution prediction.

CSTA has also installed an updated noise monitoring system. The original system consisted of four monitors developed in 1984 by Construction Engineering Research Laboratory. The upgrade, started in 1991, has added 14 Larson Davis Laboratories monitors with plans to order additional units as funding becomes available. The monitors stationed around CSTA automatically call in to the base station computer. The data collected is used to verify and update the noise prediction model, respond to noise complaints, and investigate damage claims.

CSTA conducts a daily noise assessment each morning that large caliber firings are scheduled. Weather data is collected and used to generate a predicted noise contour plot for the surrounding area. To validate the model for that particular day, a three-pound charge is detonated and the noise levels in the surrounding communities are measured. Based on these confirmed predicted/monitored levels, appropriate restrictions are implemented. If the predicted noise level is above 130 dB, the firing is postponed, to be resumed by command decision. In the range of 125 dB to 130 dB, the firing is evaluated on a case-by- case basis with approval by the Executive Officer or his designee.

No firings or detonations of any type are conducted weekdays before 6:00 AM and after 10:00 PM, Saturdays before 7:30 AM and after 3:30 PM, and Sundays and holidays. No large caliber firings and no static detonations of five pounds or more are conducted weekdays before 8:30 AM and after 10:00 PM and Saturdays before 8:30 AM and after 3:30 PM. The CSTA commander must approve all other firings.

For more information see the Point of Contact for this survey.