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HomeMy WebLinkAboutOB 1 JWA NOISE STUDY 01-04-88~ ' OLD BUSINESS · /. NO. 1 TO: FROM:' SUBJECT: . WILLIAI~ HUSTON, CIlY PlANAGER COI~UNITY DEVELOPINENT DEPARTMENT ~IWA NOISE STUDY - UPDATE RECOMMENDED ACTION Receive and file. DISCUSSION Monitortn9 Program - Attached for the Council's information is the proposed )kircraft Noise Monitoring Plan that the City's noise consultant, John Va6 Houten has transmitted to the Airport for their consideration and use in drafting their own noise test plan. When airport staff complete their own noise monitoring test plan it will be be reviewed internally by airport staff and then transmitted to the City of Tustin for our comments. Noise monitoring equipment that has been ordered by the airport has not been received yet. Once received in early January, it will take approximately two to three weeks to hire technicians resulting in the actual noise monitoring effort being delayed until late January or early February. Localized_Test Program - According to the airport, the portable Localizer Direction Antennae (LDA) is working very well. All test data has not been evaluated but once it is the FAA will review the findings and perform some flight tests. The decision to leave the temporary equipment in place and the plan for the installation of a permanent installation has not been formulated at this time. i,, J Christine A. S~i~gletE~t, Director of Community Development CAS: ts J j. j. VAN HOUTEN & ASSOCIATES, Inc. 1260 BAST KATELLA AVENq3E, ANAHEIM, CALIFORN~ 92805 (714) 635-9520 JOHN ]. VAN HOUTI~N, PR, Principal DAVID L. WII~LAND, Senior Engineer December 22, 1987 Project File 1890-87 CiTY OF TUSTIN Community Development 300 Centennial Way Tustin, CA 926 80 Department Attention' Subject,' Mr. Steven Rubin, Senior Planner Aircraft Noise Measurement Program Me th odot ogy Gentlemen · Concern has been expresSed regarding the noise .generated by flight operations at John Wayne Airport as they pass over the City of Tustin. To this end, a noise monitoring program has been proposed by the County. The purpose of this program is to: Determine the single event noise exposure levels (SENEL) and maximum noise levels (MNL) within the exterior and interior ~ living spaces of residential areas affected by the aircraft operations. Assist in the establishment of the community noise equivalent level (CNEL) contours generated by the aircraft operations. Identify the specific contribution of each aircraft type and each air carrier to the noise exposures within the residen- tial areas. Establish the specific contribution of and/or dispersion of the flight track to exposure within the residential areas. each flight track the level of noise Assist in the determination of the extent of impact (number of homes, number of people, level of exposure, etc.) caused by the aircraft operations within the residential areas. .Determine viable alter'natives in the aircraft operational profile (aircraft type, number of operations, time ef day, flight tracks, etc.) which will reduce the exterior and inte- rior noise impact within the community. Appendix I provides an City of Tustin which wil the plan may be summariz aircraft noise monitoring plan for the 1 satisfy the above objectives. Brie?!y, ed as follows' CITY OF TUSTIN PROJECT FILE 1890-87 oo Obtain the SENEL and MNL for a statistically significant num- ber of each type of aircraft on each flight track affecting the selected measurement positions. Establish the energy average SENEL and MNL for each type of aircraft on each flight track affecting the measurement posi- tions to within a 90% confidence limit of + 1-1/2 dB(A). o Calculate the CNEL for each measurement position using the operational profile provided in the EIR and Access Plan for John Wayne Airport, and the measured data obtained as part of this noise monitoring program. The attached test plan has been provided to the County to assist in their planning of the measurement effort. If you have any questions, please contact the undersigned at 714/635-9520. Very truly yours, J. j. VAN HOUTEN & ASSOCIATES, INC. ~hn J. V/an Houten /~onsultVng Engineer in Acoustics UJ JV H/rr p /- C: \WS2OO0\R EPORTS\ 1 850-99\ 1 890-87 J. J. VAN HOUTEN & ASSOCIATES, Inc. APPENDIX I Aircraft Noise City Monitoring Test of Tusti n Plan, Aircraft Noise Monitoring Test P1 an I. Selection of Noise Monitoring Positions The number and location of noise monitoring positions shall be selected with regard to the development of noise exposure con- tours and will adequately encompass the City. The following criteria shall be used in the selection process' Residences where homeowners have expressed an interest in the program shall be used where such use satisfies the test plan criteria. be Measurement positions shall have @ low background noise level (at least 10 dB below aircraft noise levels, away from and shielded from roads) ~, C · Measurement positions shall have no acoustic interference (away from vertical reflecting surfaces, no line-of-sight obstructions to the aircraft). d. Measurement positions shall be secure. II. Instrumentation All instrumentation shall be precision sound level meters per American National Standard ANSI S1 .4-1971, or latest revision thereof, and shall be calibrated prior to and following each measurement period. III. For ea ch (refer to noise event, data sheet, a. Noise source, if 1 awnmower, etc.) b. Time and date· c. Type of aircraft. Noise Measurement Procedures the following information shall be noted Enclosure 1 )' not aircraft (e.g. , car, truck, motorcycle, d. Carrier. e. Flight track (pattern). f. Type of activity (i.e. , takeoff, landing, touch-and-go, flyby) · A weather-tog shall also be maintained during the noise monitor- ing program. At least once an hour, the following information shall be noted (refer to Enclosure 2): a. Time and date. b. Wind speed and direction. c. Temperature. de Al.1 measurem basis to assu the data she that the' test Where interi taneously wi noise reducti following cfi Relative humidity. . ent data shall be gathered and examined on a daily re that the monitors are functioning properly, that ets are being filled out completely, and to assure procedure is being followed correctly. or noise measurements are to be obtained simul- th exterior measurements in order to determine the on provided by standard building construction, the teria shall be met: a · The measurement shall be obtained in a room with direct line- of-sight to the aircraft noise. b· The room shall be furnished and carpeted. Drapes, blinds, or shutters shall be kept open. c. All windows and doors to the room shall be tightly closed. d · e · There shall be no interior-generated noise sources (e.g., ventilation systems) operating during the test. The interior microphone shall be positioned three feet from the center of the window(s) at a height of 5'. f· The exterior microphone shall be positioned at a distance of 10 feet from the window at a location for which there are no reflective surfaces within 10 feet of the position. The ex- terior microphone height shall be 10 feet. IV. Interpretation of Measurement Data All measurement data shall be interpreted on a regu] ar basis. This interpretation shall include: a · b · c · Corrections for annual average weather (~emperature, windspeed and direction, relative provided by JWA personnel. conditions humidity) as Calculation of the energy average SENEL and MNL for of aircraft on each 'flight track. This shall be every measurement position and shall exclude all events for which the MNL was less than 10 dB(A) programmed noise threshold. (Refer to Enclosure 3.) ea ch type done for aircraft above th e Calculation of the noise reduction provided by the building construction at those positions for which simultaneous inte- rior and exterior noise measurements have been obtained. V. Duration of the Noise Measurement Program The noise measurement program shall continue at each of the selected positions until the energy average SENEL for each type of aircraft has been measured to within a 90% confidence limit of + 1 dB(A). (Refer to Enclosure 3.) VI. Calculation of CNEL At each measurement position, the contribution of each type of aircraft to the overall noise exposure at the site shall be cal- culated as follows' CNELi = SENELi + 10 log (Nd + 3Ne + 10 Nh) - 49.4 dB, where, SEN EL = i average SENEL for the i-th aircraft type, as deter- mined in Section V, above Nd = number of daytime (7:00 am - 7'00 pm) operations of the i-th type of aircraft Ne = number of evening (7'00 pm- 10'00 pm) operations of the i-th aircraft type Nn = number of nighttime (10'00 pm - 7'00 am) operations of the i-th aircraft type The number of flight operations (Nd, tained from the Access Plan and the EIR Ne, and Ne) shall be ob- for John Wayne Airport. The overall CNEL at each measurement position is calculated by · adding together, on an energy basis, the contributions of the in- dividual aircraft types, VII. Documentation The report of findings for the aircraft shall include the following: a · Hard copy strip-chart records and/or all measurements. b. Tabulation of the SENEL and MNL for each position. c. Calculation of CNEL and noise reduction position. noise monitoring program d. Evidence of calibrati-on of equipment measurement period. e · instrument printouts of Certification that the manufacturer's specifications prior to the test. all aircraft events at at each measurement before and after each instrumentation meets the wi thin the one-year period f. Certification that the measureme'nts are true and accurate· ENCLOSURE 1 Aircrsft Noise Messurement Ds ts Sheet 0 ENCLOSURE 2 Weather Log Ds ts Sheet Tim~ Wind Speed Wind I)irection Position: Operator: Date: TCmp e ra~J_E~ R¢l. Humidity ENCLOSURE 3 Calcul@tion Procedures ,o 0 ' 0 0 ~ 0 ..~ 0 4-~ 0 0 0 40 ::> oo ~ o o +l 0 '~ © C_", o (D 0 -,-t c~ II 0 o t',,l o > 0