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HomeMy WebLinkAbout30 HughesGood evening, my name is Dwight Hughes and I reside between Sequim and Port Townsend. I have a professional mechanical engineering license with the State of Washington and have done a base line perimeter acoustical study of the Jefferson County Shooting Range Operated by the Jefferson County Sportsmen's Association (JCSA). The purpose of the study was to have a basis for evaluation of future changes made to the range to modify the acoustical signature. That study will be part of the ongoing operating permit process with the county so I will not go into details of it here because the numbers and calculations are frankly boring and confusing to all but engineers and safety professionals. I am aware that percussive sounds like those produced by firearms discharge are contentiously debated so I am giving some solid comparisons of the sound level readings taken at the perimeter of the range and comparing them to other sounds that people are familiar with. When doing this survey we used the highest intensity rifle cartridge available to get the maximum acoustic signature possible as well as other lower acoustic level firearms. This high intensity firearm is extremely rarely fired at the range and the survey fired half as many rounds as are typically fired in a year. Typically these high intensity cartridge rifles and other high power rifles make up less than ten percent of the rounds fired on a range. Medium caliber rifles compose about twenty percent, pistol caliber rifles and pistols about thirty percent, shotguns about twenty percent, and 22 long rifle rifles and pistols the remainder. Firearm acoustic signatures are brief, lasting less than two tenths of a second, considerably shorter than a bus or truck passing you on the sidewalk at one to two seconds or a lawn mower which is relatively continuous. These other devices are mentioned because the highest acoustic signature measured on the perimeter of the JCSA range was in the range given by government publications for these devices' s acoustic signature and less than a leaf blower or chain saw. The medium rifle, pistol caliber, and shotgun signatures measured were in line with a vacuum cleaner or heavy non truck traffic and the 22 long rifle signatures were less than a normal conversation. This is at the perimeter of the range and the power of the sound decreases with an inverse squared rate as it travels outward from there. The measured sound of the highest acoustical signature from the range at the point next to South Jacob Miller Road is comparable to the signature from the garbage trucks going to the transfer station along Jacob Miller Road at the same point. These are facts, the signatures were measured with calibrated equipment and the comparisons are from government sources. Additionally a four hour pistol and carbine match was measured at the closest perimeter point of the range with samples data logged every second and the average of those samples or time weighted average was comparable to those I have seen data logged in open plan offices with the maximum values comparable to a vacuum cleaner or garbage disposal. So despite the fact that acoustical levels generated from recreational shooting are exempted from noise regulation by Washington State law the measured levels at the JCSA range perimeter are actually low and comparable to other lawful activities in the county. Requiring any additional acoustical baffling equipment is not required when the acoustic levels are at or below other lawful activities but JCSA is proactively working with the county to add abatement baffles to reduce the highest level acoustic firearms. The planning commission advisory board has also proposed high fences whose only use will be to keep wildlife from utilizing the range to their benefit. The deer and other animals which wander through will be stopped by a fence and they regularly wander the JCSA range and other ranges in the state. Additionally requiring expensive security fence instead of signage or standard fencing would require the county to require a similar fence on all properties with an equal or greater hazard such as airports and even highways since they are a greater threat to life than trespassing on a shooting range. Requiring shooting ranges to have fences that are not required of other similar hazard facilities is discrimination and will result in lawsuits for that discrimination. The environmental discharges of firearms on shooting ranges are already regulated by Washington State Law and no additional monitoring of chemicals or non -regulatory driven setbacks from water are required. To establish additional requirements or setbacks water without specific scientifically identifiable hazards (most particularly when fueling of vessels is allowed on water) would discriminate against shooting ranges and will result in lawsuits for that discrimination. In summary JCSA has operated a shooting range on county property to the huge benefit of both the county and local and regional populace. If the planning commission choses to cater to the wishes of those who want to increase the expense and complexity of building or maintaining a shooting range without scientifically identifiable principles to back those expenses they will open the county to legal action without any benefit and endanger a county resource. Sound Level Chart Percelved Sound Level sound Level Exarnples Leel Blrxwer Reference fro idc iI Iiy E.,Oijolllla All {;['souk..,, Kiwid, Mill .JEFFERSON COUNTY DCD d8 tile. PAINFULLY 160 2x 10 laevrorks at 3 feet LOUD 150 jet at takeoff 140 2x 108 tnresnakl of pain OSHA limit for impulse noise 1-30 power drill 120 2x107 1hunder a r 110 auto horn at 1 meter 90-105 dB last bim"r a1 operators ear ,00 2 M 1 Q6 .ir11GYh'n10t)IIO _ 90 diesel truck, Wd blender 90d9 051 ,4 p@frGliiSSltillO Crxp6SurQ lirnd 60 2x10 garbage disposal 70 vacuum cleaner 62-75 d€] Leal blower of 50 feel MODERATELY 60 2x 104 ordinary convorsation LOUD 50 average home 40 2x103 lobrary QUIET 3A q nef odnverSalion VERY QUIET 20 2x102 soft whisper 10 rusllrng Naves BARELY AUDIBLE 0 2x10' lhresttokl of hearing M= tog �F';i. �rsC.rr Pas, ale fro idc iI Iiy E.,Oijolllla All {;['souk..,, Kiwid, Mill .JEFFERSON COUNTY DCD