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1992-24152-Minutes for Meeting May 20,1992 Recorded 7/15/199292-24152 0118-11'3 PUBLIC HEARING COATS' NOISE VARIANCE REQUEST PJ 4 DESCHUTES COUNTY BOARD OF COMMISSIONERS'1'P May 20, 1992 Chairman Maudlin called the meeting to order at 5:30 p.m. Board members in attendance were: Dick Maudlin, Tom Throop and Nancy Pope Schlangen. Also present were: Dave Leslie, Planner and Rick Isham, County Counsel. Before the Board was consideration of a noise variance application of R. L. Coats to vary the hours of operation of his hot mix asphalt plant, equipment and trucks at his property located at 2975 NW Skyline Ranch Road in Bend. Chairman Maudlin said this variance would allow Mr. Coats to bid on a State Highway job which required that the work be done between 10 p.m. and 6 a.m., Monday through Friday, from June 1, 1992, through August 1, 1992. Chairman Maudlin opened the public hearing and asked for a staff report from Dave Leslie. Mr. Leslie said notices were sent out on this hearing in anticipation that there would be time for the staff to prepare an adequate staff analysis of the request prior to this hearing. However, information had just now been submitted from the applicant's noise engineer from a noise sampling done the previous day. He had discussed with the applicant, the need for additional analysis and information in writing based upon the criteria for a variance request, specifically Deschutes County Code Section 808, Chapter 19.108, and ORS 467.060. That information had also just been submitted at this meeting. Therefore, he recommended that the Board take testimony only from those individuals who could not attend a future hearing, and then continue this hearing to June 3, 1992, at 5:30 p.m., so that a written staff report could be prepared and considered by the Board and the public before the hearing. This date had been discussed with the applicant and some members of the public prior to this hearing, and they were satisfied with the continuance date. There was now some concern regarding the timing of the contract. His discussion with ODOT staff indicated that the contract bidding would be opened on May 28 and that a contract would not be let for at least two or three weeks after that date. Chairman Maudlin asked for testimony from anyone who could not attend the continued hearing on June 3, 1992. Robert Coats, applicant, said Mr. Duble, who did the noise study, could not attend the future hearing and asked if he could testify that evening. He then requested that the Board move the hearing date up since he needed to know by May 28th whether he would receive the variance in order to bid the ODO p O* MD PAGE 1 MINUTES: 5-20-92 '" �` 0118-11'74 Commissioner Throop asked what the time frame of the variance was. Mr. Coats said it had been shortened to four days a week instead of five (Monday through Thursday), June 30 - September 30, 1992, however said he could hone the request even closer. He didn't anticipate starting work before 10 p.m. He submitted some handouts to the Board. Albert G. Duble, P.E., Acoustical Engineer, 16905 NE Kings Grey Road, Newberg, 97132, testified that he had conducted a noise study concerning the night time operation of the asphalt batch plant. He read from his Environmental Noise Analysis report which is attached to these minutes. Commissioner Maudlin asked staff if the ambient noise level was restricted so as not to exceed the level of 10 over the ambient noise at any time? Mr. Leslie stated that for a new industrial site, noise was limited to 10 dba above the ambient. Rick Isham pointed out that the County ordinance was a prohibition ordinance as opposed to a DEQ level. Ken Buxton, 2861 N.W. Polarstar, Bend, OR 97701, testified that it was not the plant that affected him as much as the trucks using the Shevlin Park Road. He said that at present, it was nearly intolerable during the daytime, and he felt any increase would be unbearable with the constant activity of the trucks and the noise of the jake brakes. Susanne Walsh, 2897 N.W. Polarstar, Bend, OR 97701, stated that she and her family were seriously affected by the noise of the trucks. She said that during the summer months, sleeping would be difficult since the weather would be warm and require that windows be open. She stated that the noise from the trucks woke her at 6 a.m. John Jabaley, 2621 N.W. Marken Street, Bend, OR 97701, said that the trucks were the problem. He and his family moved to this location approximately one month ago and were unaware of the noise problem. They would probably not have moved there if they had known the noise level was so high. Mary Dyer, 19135 Buck Drive, Bend, OR 97701, stated she would present her tax loss data at the continuance. Chairman Maudlin set May 27, 5 p.m. as the date for the continuance. He requested that those in the audience sign a sheet indicating their interest in attending. He said a notice would be mailed to those individuals noting the date, place, and time. A notice would also be placed in the newspaper. Commissioner Schlangen indicated that testimony could be given at the time of the meeting, or mailed to the Board of Commissioners, or that individuals who could not attend, could give testimony during the present meeting. PAGE 2 MINUTES: 5-20-92 Rebecca Wolle, 63404 Fawn Lane, Bend, OR 97701, cartlllMi tAsk what the noise level of a barking dog would be. There were mostly five -acre parcels where she lived. During summer nights with the windows open, barking dogs would wake people, therefore, a noise level of 50 decibels would be very disruptive. Chairman Maudlin stated that even though he lived quite a ways from Tumalo, he could hear barking dogs in Tumalo. Mr. Duble stated the decibel level would depend on the number of dogs and the distance. Ms. Wolle said her point was that residents of the area would not be sleeping well at night from the increased noise caused by the increased hours of operation. Since there was no further testimony, the meeting was continued to May 27, 5 p.m. in the Juvenile Justice Center. DATED this 3 day of , 1992, by the Board of Commissioners of Deschutes Co tv, re n. ss ATTEST: Nancy Pohle Sdhiangd�n, Commiss&oner `I G� aeco4r�d�ing Secretary /ic'k�NZaudlin,_ Chairman PAGE 3 MINUTES: 5-20-92 0118-1176 DESCHUTES COUNTY, OREGON May 1992 by Albert G. Duble, P.E., Acoustical Engineer Newberg, Oregon 0118-1177 MAY 19, 1992 This noise analysis was conducted to support the Company request for a variance in operating hours to allow nighttime operation of the asphalt batch plant. Ambient noise was measured as near as possible to two residences east of the present plant, across the Deschutes River Canyon. Average L50 ambient noise between 10 PM and 6 AM was 36 dBA. This aggregate production site has been in operation for many years, before the residences on the east bluff were constructed, therefore the State DEQ nighttime noise standard is 50 dBA. Present asphalt plant noise was measured 100 feet from the major noise sources and the data used to predict future nighttime noise across the canyon at the Elkins residence. Predicted noise was 61 dBA at both the Elkins residence and another cedar home just south of Elkins, both located close to the bluff above the river. This level is 11 dBA above the nighttime standard, therefore a noise barrier was introduced close to the asphalt drum burner. The new noise level with the trial barrier was 51 dBA. With a well designed burner platform enclosure, noise barrier, or both, it should be possible to meet the nighttime DEQ 50 dBA standard across the canyon. Noise at the two nearest residences was monitored overnight using a Larson -Davis Labs Model 700 automatic noise analyzer, specially modified and calibrated by the manufacturer to meet the Type 1 precision sound level meter specification (ANSI S1.4A - 1985). This analyzer samples the microphone signals twice a second, stores the data and prints to memory a statistical analysis at a preset time interval which, in this case was hourly. At the end of each data session, the stored data is printed to a portable computer printer for a permanent record. The measurement descriptor is the A -weighted decibel (dBA) which is used by the Oregon State DEQ in their noise standard. 1 ©118-11'78 The microphone was a Bruel & Kjaer precision 1/2 inch electret condenser type, calibrated using the Bruel & Kjaer Model 4230, 1000 Hz, 94 decibel acoustic calibrator. The microphone was attached to a 5 foot high tripod which were placed on the ground within fifty feet of each residence. Weather conditions during the tests were generally good with mild temperatures between 44 and 68 degrees. There were only light overnight sprinkles and wind was generally from the northwest at 5 to 10 MPH. The microphone was protected by an efficient windscreen, and no corrections to the data were required for atmospheric conditions. Data printouts attached show PM and 6 AM, the hours of proposed operation. the ambient noise between 10 asphalt batch plant Average L50 ambient noise as measured on the west bluff between 10 PM and 6 AM was 36 dBA. This nighttime noise is low and normal for high desert country far from highways or airports. The same or very near ambient noise would exist across the canyon on the east bluff. Present ambient noise with the gravel crusher and asphalt plant operating was measured at the Neidzwiecke residence at 19425 Klippel Road, south-southwest of the Cake Pit. Noise measured here was just at the nighttime standard at 50 dBA. Future noise due from the asphalt batch plant was calculated using the noise prediction program called "Noisecalc" developed by the State of New York. The program includes standard atmospheric absorption, inverse square spreading (normal distance) losses, barriers where present, and allows for entry of special excess attenuations due to forest and ground cover, and for direct entry of source octave band noise levels. (Appendix A shows computer printouts for the data used to predict noise at the Elkins residence across the canyon. Both the source and the receiver in this case are situated on opposite bluffs of the Deschutes River canyon. 2 0118-11"79 Clear sight -lines exist between these points. An average eastern Oregon temperature and humidity of 49 degrees F and 25 percent was used for prediction. High frequency noise in dry climates dissipates more rapidly than in more humid areas. Asphalt batch plant noise levels used for computer predictions were obtained from on-site testing with the burner and exhaust fan operating. This source data is presented in Appendix B of this report. The on -axis degree noise position was used for the drum burner as it was coincident with the two residences across the canyon. Predicted noise on the east river canyon bluff was 61 dBA. (See computer printouts attached). The asphalt plant at the DEQ nighttime standard of 50 dBA will be approximately 14 dBA above the ambient noise. At this level, it will be noticeable to nearby residents at night. Impact on residents over the three month operating period should be less in the residences with windows closed, and the short operating time should increase tolerance to the noise. Noise at the Niedzwiecke residence south-southwest of the plant should decrease below the nighttime standard of 50 dBA as the gravel crusher will not operate at night. The probable noise level will be about 47 dBA. Present asphalt plant noise exceeds the nighttime DEQ noise standard of 50 dBA by it dBA, but with a well designed burner platform enclosure, noise barrier, or both, it should be possible to meet the standard across the canyon. 3 1. IL �F q:r i1 2 v Wiz, f DOE LN o / •{ f9� ' !Y �e Tumalo Butte ( 1 \ PurA4 H \ { r r ,,�' I � PSS♦ O,K `� u ���- I wbre Bui w .I OQ♦ti Q KEENAN N� 1 ,I a H Oq CT T 9 4 QQ �MMIT LYS` to DR CHANEY RD j C11 N Fid* v�5 uri 1-QOO i`P�� /f 0QQ P QO . .P \ HALF y Ij r mg��NER r� F4, P, -JF 1 9�G "o I R D cF I 3 Z —t-1 2- BEND d I'SAWYE' . 1 F RIVER EDGE GOLF i 0118-1181 A 63 12& Z5 -Q. 59M 1000 2000 4000 8000 90 94 99 89 77 72 66 58 49 DATA REPORT LARSON-DAVIS LABS -- MODEL 700 05/20/92 08:47:53 SN 70OB1085 PACE 1 Dose 3200.0 Proj 2136.0 LVL 45.5 Lc = 3"1 ( l 4 QAA Time 0011:59:58 Lmax 86.0 OV LD 005 RMS Ex 0001 Pk Ex 000 S 1 Memory 5646.0 8 5 L110 01 39.0 L5 -a 3k' L50 35.5 L90 34.0 SETUP DATA Detc FAST hUnagt Pk=0 Crit 32.0 Thld 32.0 Exch 3 LDL =0 PkSThldd 32.0 Hyst 5 Run date 05/19 Stop date 05/20 Run time 1 19:00 Stop time 1 07:00 Run time 2 99:00 Stop time 2 99:00 Excd =0 Intv =1 Time 01:00 Auto -Stop =0 Ln a Hist -0 Save Pk -0 Per 30.0 Cal 13.5 Ver 1.410 0118-1182 INTV REPORT U118 183 • CARSON-DAVIS LABS -- MODEL 700 1 05/20/92 08:51:02 SN 70OB1085 PACE 1 Cnt LVL' SEL Lmax Lpk Lmin Date Time Dur Ex Pk Ov 1 38.0 74,0 57,5 81.0 21.5 19 MAY 19:00:01 1:00 h:m 1 1 0 L01 - 49.0 1,10 - 39,5 L50 = 36.0 L90 = 34.0 2 37,0 72.5 56.5 70.5 32.5 19 MAY 20:00:01 1:00 h:m 0 0 0 L01 - 46.5 L10 - 38.0 L50 = 35.5 L90 = 34.0 3 37.0 72.5 47,0 58.5 33.0 19 MAY 21:00:01 1:00 h:m 0 0 0 L01 = 42.0 L10 = 39.5 L50 = 36.0 L90 = 34.0 4 36.0 71.5 52.0 61.0 32.5 19 MAY 22:00:01 1:00 h:m 0 0 0 L01 - 44.5 L10 - 37.0 L50 = 35.0 L90 = 34.0 5 35.5 71.5 46.5 58.0 33.0 19 MAY 23:00:01 1:00 h:m 0 0 0 L01 - 41.0 L10 = 36.5 L50 - 35,5 L90 = 34.5 6 35.5 71.0 44.5 59.5 33.0 20 MAY 0:00:01 1:00 h:m 0 0 0 LOS - 38.0 L10 - 36.5 L50 = 35,5 L90 = 34.5 7 36.5 72.0 50.5 63.5 33.0 20 MAY 1:00:01 1:00 h:m 0 0 0 L01 = 41.5 L10 = 38.5 L50 = 36.0 L90 = 34.5 8 34.5 70.5 42.5 56.5 32.0 20 MAY 2:00:01 1:00 h:m 0 0 0 L01 - 39.5 L10 - 36.5 L50 - 34.0 L90 - 33.0 9 34.5 70.0 43.5 58.0 32.0 20 MAY 3:00:01 1:00 h:m 0 0 0 L01 - 38.5 L10 - 35.5 L50 - 34.0 L90 = 33.5 10 38.0 73.5 58.0 68.5 33.0 20 MAY 4:00:01 1:00 h:m 0 0 0 L01 - 50.0 L10 = 38.0 L50 = 35.0 L90 = 34.0 11 37.5 73.0 62.0 78.0 34.0 20 MAY 5:00:01 1:00 h:m 0 0 0 L01 - 46.5 L10 - 37.5 L50 - 36.0 L90 = 35.0 12 55,5 91.0 L010- 54.5 34L1020 46.5 6:L5001 40.09 h:m L900= 35.5 99999 *Lv4 = Lei JA 0118-1184 * RESULTS * ASPHALT PLANT NOISE TO ELKINS RESIDENCE ACROSS RIVER CANYON AT 1500 FEET WITH ATMOSPHERIC ABSORPTION AT 49 DEG F AND 25 PERCENT R.H. AT RECEIVER # 1 ELKINS WITH THE BACKGROUND NOISE (IF ANY) SOUND PRESSURE LEVEL = +76.8 DB SOUND LEVEL = +61.5 DBA WITHOUT THE BACKGROUND NOISE SOUND PRESSURE LEVEL = +76.8 DB SOUND LEVEL = +61.5 DBA THE OCTAVE BAND SOUND PRESSURE LEVELS ARE: 31.5 63 125 250 500 1K 2K 4K 8K 16K HERTZ +0.0 +70.4 +75.3 +65.0 +52.4 +45.1 +30.5 +0.0 +0.0 +0.0 THE SOURCES WHOSE A -WT CONTRIBUTIONS ARE WITHIN 10 DB OF THE TOTAL SOURCE SOUND LEVEL AT THE RECEIVER LOCATION, ARE: SOURCE # 1 , ASPHALT, CONTRIBUTES: SOUND PRESSURE LEVEL = +76.8 DB SOUND LEVEL = +61.5 DBA THE OCTAVE BAND SOUND PRESSURE LEVELS ARE: 31.5 63 125 250 500 1K 2K 4K 8K 16K HERTZ +0.0 +70.4 +75.3 +65.0 +52.4 +45.1 +30.5 +0.0 +0.0 +0.0 RESULTS SUMMARY WITH BACKGROUND NOISE (IF ANY) RECEIVER S.PRESSURE LEV.(DB) SOUND LEVEL (DBA) # 1 ELKINS +76.8 +61.5 I * RESULTS * 0118-1185 ASPHALT PLANT NOISE TO ELKINS RESIDENCE AT 1500 FEET WITH 16 FOOT HIGH BARRIER 12 FEET FROM BURNER WITH 49 DEG F AND 25 R.H. ATMOSPHERIC ABSORPTION AT RECEIVER # 1 ELKINS WITH THE BACKGROUND NOISE (IF ANY) SOUND PRESSURE LEVEL = +68.0 DB SOUND LEVEL = +51.4 DBA WITHOUT THE BACKGROUND NOISE SOUND PRESSURE LEVEL = +68.0 DB SOUND LEVEL = +51.4 DBA THE OCTAVE BAND SOUND PRESSURE LEVELS ARE: 31.5 63 125 250 500 1K 2K 4K 8K 16K HERTZ +0.0 +63.0 +66.1 +53.5 +38.1 +27.8 +10.3 +0.0 +0.0 +0.0 THE SOURCES WHOSE A -WT CONTRIBUTIONS ARE WITHIN 10 DB OF THE TOTAL SOURCE SOUND LEVEL AT THE RECEIVER LOCATION, ARE: SOURCE # 1 , ASPHALT, CONTRIBUTES: SOUND PRESSURE LEVEL = +68.0 DB SOUND LEVEL = +51.4 DBA THE OCTAVE BAND SOUND PRESSURE LEVELS ARE: 31.5 63 125 250 500 1K 2K 4K 8K 16K HERTZ +0.0 +63.0 +66.1 +53.5 +38.1 +27.8 +10.3 +0.0 +0.0 +0.0 RESULTS SUMMARY WITH BACKGROUND NOISE (IF ANY) RECEIVER S.PRESSURE LEV.(DB) SOUND LEVEL (DBA) # 1 ELKINS +68.0 51.4 �C