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HomeMy WebLinkAbout3.0 Annual ReviewFred Jarman From: Phil Vaughan [phil c©pvcmi.corn] Sent: Thursday, March 04, 2010 3:29 PM To: Fred Jarman Cc: Tom Fiore Subject: Williams Una Compressor Station- Resolution 2008-137 Attachments: GarfCtyReso2008-137-UnaCompressorStation pdf; 3752-UNA Compressor Station-2009NoiseStudy. pdf Fred, Please find attached documents in regards to the Williams Production RMT Company Una Compressor Station This project was approved by the County Commissioners via Resolution 2008-137. Please find this document attached. Condition 12 notes that "An annual review shall be completed one year from issuance of the Special Use Permit. Such review shall include the site compliance with Industrial Performance Standards and the applicant shall be required to submit a noise study which analyzes the noise levels of the proposal once the site becomes operational." I have attached the noise study prepared by EDI dated October 2009 concluding that the Una Compressor Station is operating within COGCC rule 802 requirements. Please let me know if you have additional questions regarding this information. Sincerely, Phil Vaughan Phil Vaughan Construction Management, Inc. 1038 County Road 323 Rifle, CO 81650 970-625-5350 UNA EXISTING NOISE LEVEL UNA COMPRESSOR STATION WILLIAMS PRODUCTION RMT COMPANY PARACHUTE, COLORADO 8127/09 to 8/29/09 October 2009 Prepared by Howard N. McGregor ediengineering dynamics incorporated EDr Job No C3752 Page 1 of 9 3925 S. Kalamath St., Englewood, Colorado 80110 • voice: 303-761-4367 • fax: 303-761-4379 I. INTRODUCTION UNA d ■ engineering dynamics e 1 incorporated This report describes the work conducted by Engineering Dynamics Inc. which consisted of measuring the noise emissions from the Williams Production RMT Company UNA Gas Compression Facility located in Parachute, Colorado The work was requested by Tom Fiore, Plant Manager, Williams, 4289 County Rock 215, Parachute. Colorado. The noise measurements were started on August 25, 2009 and completed on August 27, 2009. The work consisted of two measurement protocols 1. Long term 47 -hour duration noise measurements at three locations around the UNA Compressor Facility using instruments that measured and stored in memory the average dB(A) noise level for each and every minute during the entire 47 -hour long measurement interval. 2. Measurement of the frequency characteristics of the noise at three locations with a sound level meter/analyzer allowing the noise emissions from the compressor station to be analyzed in discrete % octave bands. The %octave measurements assist in the identification of the engine/compressor/heat exchanger components that are the controlling noise sources. During the measurement interval, the two engine/compressor units were in operation. These units had the heat exchanger and cooling fans facing in a southerly direction. Several other engine/compressor units are in the process of being assembled at the UNA Facility which would increase the total noise emission levels Each of the two engine/compressor units is housed in a noise control/reduction enclosure that completely encloses the engine/compressor. The heat exchanger unit intake and discharge are baffled to reduce fan noise. The Colorado Oil and Gas Conservation Commission (COGCC) has regulations establishing allowable noise emission based on the zoning of the adjacent properties and the time of day. These regulations are in Section 802 of the COGCC regulation. For the UNA Facility the noise emission limits for the UNA Facility is 55 dB(A) during the daytime and 50 dB(A) during the nighttime. There should be no difference between the magnitude of the noise emission from a gas compression facility such as the UNA Station during the daytime or nighttime. In general, daytime noise levels tend to be higher than nighttime levels due to the contribution and addition of other noise such as from local vehicle traffic and on-site services vehicles and from Garfield County Road 306 EDI Job No. C3752 Page 2 of 9 3925 S. Kalamath St., Englewood, Colorado 80110 • voice: 303-761-4367 • fax: 303-761-4379 di engineering dynamics e incorporated 11. MEASUREMENT LOCATIONS A. Long Term Measurements, Figure 2 1. Location 1 (0031) At west property line and about 450 ft on the south side of CR306. Distance from nearest enginelcompressor enclosure was 450 ft. in a north/northwest direction. Only the taps of the compressor buildings were visible. This site was subjected to traffic noise from CR306. 2. Location 2 (0032) South of fan end of the two existing engine/compressor buildings at a distance of 350 ft. in a direct line - of -sight from the noise monitor to the two buildings and about 30 fthigher than the ground level of the two buildings. 3. Location 3 (0027) On UNA property south/southwest from the two engine compressor buildings at a distance of 300 ft. and a direct line -of -sight from the noise monitor to the two buildings at the same elevation as the buildings and more exposed to noise coming from the side of the engine/compressor building. B. Sound Level Meter/Analyzer 1. 100 ft. in front of the fan end on a line between the two engine/compressor buildings, 2. 100 ft. directly behind the engine/compressor buildings. 3. 100 ft. west from the side of the most western engine/compressor building similar to Location 3 above. UNA EDI Job No. C3752 Page 3 of 9 3925 S. Kalamath St., Englewood, Colorado 80110 • voice: 303-761-4367 • fax: 303-761-4379 ill engineering d dynamics e1 incorporated III. MEASUREMENT EQUIPMENT 1. Noise Monitors -- Quest Model M-39 a. Location 1, Serial Number 0031 b. Location 2, Serial Number 0032 c. Location 3, Serial Number 0027 The Quest Model M-39 noise monitors are a Type I instrument and have tolerance limits of ± 1 dB in the mid -frequency range and ± 1.5 at the low frequencies. UNA 2. Noise Monitor Programming a. Weighting — A b. Response — Slow c. Measurement Interval — One (1) Minute Samples d. Hourly Events e. One Minute Average Level f. Exceedance Level —1 % increments g. Exceedance Level Range —1 % to 99% 3. Calibrator — Quest Model QC -20 Serial Number: QIG050085, Calibration Date: 02/26/09 The Quest Model QC -20 acoustic calibrator has an accuracy of ± 0.3 dB. This means that when the QC - 20 acoustic calibrator is placed on the microphone of a noise measuring instrument and the instrument adjusted to read 114.0 or 94.0, the actual calibration values can be between, 113.7/114.3 or 93.7/94.3 at the frequency at which the calibrator is set. This means that at other frequencies the measuring instrument, such as a sound level meter, could have errors greater than ± 0.3 dB. However, when such instruments are calibrated in Engineering Dynamics's Laboratory, the entire frequency range of the instrument is tested for accuracy using equipment traceable to the National Institute of Standards and Technology. 4. Sound Level Meter/Analyzer — Quest Sound Pro Serial Number RTD080019, Calibration Date: 08104/09 EDI Job No. C3752 Page 4 of 9 3925 S. Kalamath St., Englewood, Colorado 80110 • voice: 303-761-4367 • fax: 303-761-4379 1 engineering dynamics e (incorporated IV. MEASUREMENT RESULTS A. Long Term Measurements Table 1 presents the long term noise data recorded at the three locations around the two operating engine/compressor buildings. The data in the columns under the heading titled," dB(A) Exceedance Levels" are a measure of the statistical distribution of the noise for each and every one -minute interval of the forty- eight hour long measurement time from 8/25/09 to 8/27109. UNA in addition the last two columns in Table 1 show the average level for the daytime (7:0Oam to 7:OOpm) and the nighttime (7:OOpm to 7:OOam) during the 48 -hours of measurements. It can be seen that the average daytime and nighttime noise levels are almost equal. In determining the average daytime level at Site 1, high level one -minute dB levels were thrown out because they were assumed to be from vehicles on CR 306. It was observed that there was considerable gas field related truck traffic which produced values as high as 60 dB(A) 1 UNA Compressor Station Noise Emission Levels @ 350 ft. and 450 ft. Location Distance Duration/Hrs dB(A) Exceedance Levels — Percentiles % Average 1 10 50 90 Day Night Site 1 450 ft. 47 68 55 45 40 48 45 , Site 2 350 ft. 47 55 50 48 43 48 47 Site 3 300 ft. 46 57 55 54 51 54 53 Measurements were taken with a sound level/analyzer meter in addition to the long duration measurements which have been presented in Table 1. Both A, C and "A octave dB values were measured at three location around the compressor station. These results are presented in Figure 1. Section 802 of the Colorado Oil and Gas Conservation Commission (COGCC) regulation limits the maximum allowable noise level based on the zoning of the adjacent properties. Also, the noise limits are those values measured at 350 ft from the noise source or the noise emitter's property line which ever is greater. A copy of the COGCC Section 802 is attached to this report. The dB values presented in Figure 1 can be extrapolated to 350 ft. using the formula in 802-C § (1). For the 100 ft. data presented in Figure 1, the correction to 350 ft. from the 100 ft. data is a subtraction of 10.88 dB. Associated with this calculation is the condition that there are no other physical effects such as terrain, vegetation, wind and temperature gradients that would cause the actual measured value to be different. Far example. at distances greater than 1000 ft., the effect of wind alone can be plus or minus 10 dB. There are several ways to view or understand the meaning of the Exceedance Level Percentiles and the decibel value associated with each percentile. For example: The 1 Percentile Only one percent of the total measurement time, in this case. 47 hours, did the noise exceed the decibel value presented in Table 1. For almost all gas compression stations the one percentile levels are caused by local vehicle traffic. aircraft overhead, wildlife, wind, thunder and venting. Also, higher than normal noise levels are produced when the noise monitoring instrument is carried to the measurement site and set in place and similarly when the instrument is retrieved. Site 1 was affected by vehicle traffic noise because it was located only 200 ft. from CR 306. The 10th Percentile This percentile includes all of the high noise values of the one -percentile plus all of the noise that occurred more than 10% of the total time of 47 hours. Frequent nearby motor vehicle traffic would be a major contributor to this percentile value The 50"' Percentile EDI Job No C3752 Page 6of9 3925 S. Kalamath St., Englewood, Colorado 80110 • voice: 303-7614367 • fax: 303-761-4379 ngineering or incorporated Similar to the Class Average where half of the students get a better grade and half of the students get a lower grade. For gas compression facilities, the 50th values are in most cases getting close to the actual noise level caused by the station. Daytime one -site construction activities would affect the 50th percentile value as would service trucks. The 90"' Percentile Very close to the constant noise level produced by a gas compressor facility when almost all of the varying noise sources are not present. In other words, the 90h percentile is that dB value or lesser value that would occur for each and every one -minute average over the entire 47 hour long measurement period or 2538 minutes out of the total of 2820 minutes Section 802, paragraph C of the COGCC Regulations states "In the hours between 7.00am and the next 7 OOpm, the noise permitted below may be increased ten (10) dB(A) for a period not to exceed fifteen (15) minutes in any one (1) hour period. This is equivalent to 2% of the daytime hours and 19 % of the total 24- hour day. Ignoring the requirement that the 10 dB(A) exceedance can only occur in one 15 -minute increment during the daytime, this 10 dB(A) limit could be compared with the requirement that the L10 exceedance value can not be greater than 10 dB(A) over the Lgo limit for the specific Zone in COGCC 802 paragraph C Interestingly, there is a limited correlation between the two as can be seen in Table 1 Sound Level Meter/Analyzer Measurement. Figure 1 presents the sound levels in '% octave bands. A -weighted, and C -weighted as measured at three locations around the UNA Compressor Facility. These short term one -minute averages are in reasonable agreement with the long term measurements taken with the noise monitoring instruments. The % octave band data presented in Figure 1 are the actual decibel values, corrections to A -weighting and C -weighting have not been made. From these values the A and C weighted values can be computed using an Excel spreadsheet. What the V] octave data show is that there are peaks in the noise spectrum at 20, 40 and 80 Hz corresponding to 1200, 2400 and 4800 rpm, which can be related to engine, fan speed or harmonics thereof The engine, a CAT 3516, has 16 cylinders and normally runs at 1200 rpm or very close to 1200 rpm resulting in a firing rpm of 4800 rpm (1200 rpm X 16 X % = 4800). This would result in a peak in the '/3 octave spectrum at 80 Hz coming from the engine exhaust pipe. Assuming the fan has eight blades and is running at 300 rpm, then the blade passage frequency would be close to the peak at 40 Hz. This peak at 40 Hz has been observed at other engine/compressor units fitted with a CAT 3516 and Air -X heat exchanger The peak at 20 Hz that occur to the front, rear and side of the unit corresponds to rpm of the CAT 3516 engine and is probably coming from the exhaust or air intake. The COGCC regulations addresses low frequency noise as measured by the C -weighting and that the decibel level must not exceed 65 dB(C) at the receptor. usually a nearby residence. Using a value of 77 dB(C) at 350 ft. from the fan end, the distance to 65 dB(C) would be 1393 ft. direct line -of -sight to the receptor residence. UNA EDI Job No. C3752 Page 6 or 9 3925 S. Kalarnath St., Englewood, Colorado 80110 • voice: 303-761-4367 • fax: 303-761-4379 ■ engineering dynamics e rincorporated V. SUMMARY The measured average noise levels at the UNA Compressor Station were: A. Long Term Noise Monitors 1. North/northwest @ 450 ft. — 48/45 dB(A) 2. South @ 350 ft. — 48/47 dB(A) 3. See Figure 2 @ 300 ft. — 54/53 dB(A) B. Short Term Sound Level Meter/Analyzer — Figure 1 1. North @ 100 ft. — 58 dB(A) 2. South @ 100 ft. — 62 dB(A) 3. East @ 100 ft. — 57 dB(A) C. Site Expansion As mentioned in the introduction, six more engine/compressors are planned for installation at the UNA Compressor Station; one new unit is already on site but not yet in any noise control enclosure or in operation at the time when the measurements reported herein were taken. If this unit and the other five are installed and inside of the same noise control building, a 4 dB(A) increase in the noise levels listed in A and B above can be expected. UNA EDI Jab No. C3752 Page 7 of 9 3925 S. Kalamath St., Englewood, Colorado 80110 • voice: 303-761.4367 • fax: 303-761-4379 80 41, 70 w :6o 9 (N 50 Z en al 0 WILLIAMS PARACHUTE UNA ■ engineering edyincorporatednamics EDI JOB N0:3752 0 77.2 DB(C) • 77-0 DBC O 75.2 DB(C) MAN DOORS OPEN 8 $2. D$ A} • 58.1 DB(A) D 57.3 DB(A) DJ MI c 1111 • 1 41L. 16 31 CAT 3516 ENGINE TEST DATE 8/27/00 BLADE FAN 63 125 250 FREO-Hr 500 K 2K 4K NORTH 100FT -- • FAN END SOUT# 100FT -- 0 REAR EAST IOOFT -- 0 RIGHT SIDE 8K FIGURE - 1 UNA UNA EDI Job No. C3752 Page 8 of 9 3925 S. Kalarnath St., Englewood, Colorado 80110 • voice: 303-761-4367 • fax: 303-761-4379 clidynamics ncorporated • Nit -1' ti:11-. Measurement Locations 8127 to 8/29, 2009 Sr/ LINA Station Figure - 2 LJNA EDI Job No. C3752 Page 9 of 9 3925 S. Kalamath St., Englewood, Colorado 80110 • voice: 303-761-4367 • fax: 303-761-4379