HMMH T E C H N I C A L M E M O R A N D U M 1. INTRODUCTION. Rita Ogden, UCSF. Gene Reindel, Bob Behr, Rhea Gundry. Date: June 24, 2015

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1 HMMH 8880 Cal Center Drive, Suite 430 Sacramento, California T E C H N I C A L M E M O R A N D U M To: Rita Ogden, UCSF From: Gene Reindel, Bob Behr, Rhea Gundry Date: Subject: Reference: UCSF Helicopter Operations Measurements and Modeled Single-Event Noise Exposure Level (SENEL) Contours in support of the Residential Sound Reduction Program (RSRP) HMMH Revised Proposal to Assist UCSF Implement RSRP at Benioff Children s Hospital, April 22, 2014 Supplemental Environmental Impact Report, UCSF Medical Center at Mission Bay - Residential Sound Reduction Program for Helicopter Operations, April 22, 2009 The purpose of this technical memorandum is to present the UCSF Medical Center Residential Sound Reduction Program (RSRP) noise contour. This RSRP contour is to be used, as described in the April 2009 Supplemental Environmental Impact Report 1 (SEIR), to determine the residential properties potentially eligible to receive treatment to mitigate the impacts, if found, from nighttime helicopter transports. 1. INTRODUCTION In conjunction with the development of the UCSF Medical Center at Mission Bay, UCSF conducted an extensive community outreach program dating back to 2001 with regard to the inclusion of a rooftop helipad to accommodate helicopter transports. This outreach program included various community meetings where medical transport staff, helicopter pilots, and consultants were available to answer community members questions and discuss the purpose and need for the helicopter transports, helicopter flight paths to and from the helipad, and the expected sound levels from helicopter transport operations. As a result of these meetings, UCSF relocated the helipad and developed the RSRP included in the San Francisco Board of Supervisors approval of the helipad in July to mitigate interior sound levels if needed. The RSRP identified: potential impacts on the community from helicopter noise, steps taken to minimize these impacts, program elements and implementation to address any further identified impacts, and changes to the program as a result of community concerns and feedback. A noise study was conducted in 2008 consisting of noise measurements in the surrounding communities and the use of the Federal Aviation Administration s (FAA) Integrated Noise Model (INM) to predict the noise levels of the projected helicopter transport operations. The results of the study were included in the SEIR. Upon completion of construction and the opening of the hospital in February 2015, the RSRP defined a startup period of 8-12 weeks to allow helicopter transport operations to reach a normal and stable level. Afterwards UCSF was to revisit the initial projected noise exposure level contour developed in the SEIR and make any adjustments to the noise contours based on actual measured noise levels and UCSF patient helicopter transport activity. 1 Supplemental Environmental Impact Report, UCSF Medical Center at Mission Bay - Residential Sound Reduction Program for Helicopter Operations, Mitigation Measure MCMB.5-4a, pp , April 22, mary%202009%20original_0.pdf

2 2. BACKGROUND UCSF Helicopter Operations Measurements and Modeled SENEL in support of the RSRP Page 2 The SEIR for the UCSF Medical Center at Mission Bay included a noise analysis to determine potential impact to the neighboring community from helicopter transport operations. The analysis included two noise metrics: Community Noise Equivalent Level (CNEL) a 24-hour average sound level that includes a projected daily average of helicopter transport operations with adjustments to the noise levels that occur during the evening and night to reflect the added intrusiveness of noise during certain times of the day. The FAA and the State of California use the 65 decibel (db) CNEL to identify the noise impact area for projects in California. Single-Event Noise Exposure Level (SENEL) a measure of the sound level from one event such as a helicopter arrival or departure. SENEL has been used in various studies to predict potential sleep awakening from nighttime events as recommended by the Federal Interagency Committee on Aviation Noise (FICAN) 3. The noise analysis of UCSF predicted helicopter transport operations determined that the 65 db CNEL contour was essentially contained within the hospital campus boundary and, more important, no residential land uses were within the 65-dB contour. Out of concern for nearby neighbors, UCSF proceeded one step further and examined potential sleep awakenings from nighttime helicopter transports using SENEL. Extensive research and noise studies show that less than 30% of the population is awakened by a single aircraft event with an interior SENEL of 80 db. Based on most homes reducing aircraft noise by at least 15 db from outside to inside, UCSF identified the 95 db SENEL as the single event exterior level that would begin to impact the community. Therefore, UCSF chose to use the 95 db SENEL contour as the basis for addressing the effects of the helicopter noise on the community. The SENEL contour in the SEIR was identified as the preliminary RSRP contour. The RSRP called for conducting noise measurements of actual helicopter transports at the UCSF Medical Center and refining or redrawing the 95 db SENEL contour after the start-up period of the helipad. This memorandum provides the results of the additional noise measurements conducted in the community. 3. NOISE MEASUREMENT PROGRAM OVERVIEW HMMH conducted noise measurements in the community including a helicopter flight demonstration to a UCSF-designated ground level location in October 2007 as inputs to the SEIR noise analyses. The measurement results assisted in the development of the RSRP and the preliminary RSRP 95 db SENEL contour. In October 2014 prior to the opening of the UCSF Medical Center at Mission Bay, HMMH conducted additional noise measurements at six community sites during a demonstration of helicopter flights to the rooftop helipad. After the completion of the RSRP start-up period, HMMH prepared for and setup six noise monitor sites on April 22, 2015 to measure UCSF Medical Center helicopter transport activity. Five of the sites were at the same or nearly the same exact location as those selected by UCSF for the October 2014 measurements. One of the original sites (Site B) was not available during this measurement period. An additional site (Site H) was located on the south wing of the hospital near Mariposa St. The site locations of the April/May 2015 measurements are shown in Figure 1. The noise monitors collected data for nine full days with all but one monitor removed from their locations on May 2 (The final site was not removed until May 5 due to the residents being unavailable). During the time period from April 22 through May 1, nine (9) helicopter transports occurred at the UCSF helipad. The following sections provide information on equipment setup, records of UCSF helicopter operations, the measurement results at each location, and a comparison 0f the actual measurements to projected modeled results. 3 Effects of Aviation Noise on Awakenings from Sleep, Federal Interagency Committee on Aviation Noise (FICAN), June

3 Page 3 4. NOISE MEASUREMENT SITE SETUP On April 22 HMMH personnel deployed a Larson Davis LD831 noise monitor mounted on a tripod at each of the six locations listed in Table 1 and shown in Figure 1. Each monitor was connected to an external power source to avoid the need to replace batteries during the extended measurement period. Each monitor was setup to collect and store the average sound level measured each second. Photos of the site setups at each location are included in the appendix. Table 1. UCSF Helicopter Measurement Site Locations Site Address Location Relationship to Helipad A 615 Tennessee St. Roof ~1,000 feet south C 1206 Mariposa St. Deck ~1,800 feet southwest D Mission Creek Houseboat Slip 53 Deck ~2,500 feet northwest E 420 Mission Bay Blvd 15 th floor deck ~1,800 feet northeast F 808 Minnesota St. Deck ~2,400 feet south H Benioff Children s Hospital Roof ~700 feet south Source: HMMH, UCSF, April-May 2015

4 Page 4 Figure 1. UCSF Helicopter Noise Measurement Locations Source: HMMH, April-May 2015

5 Page 5 5. UCSF HELICOPTER OPERATIONS AND TRANSPORT LOGS UCSF, as part of its normal helicopter transport procedures, maintains a log of helicopter operations to and from the UCSF helipad. The log indicates the date, times of arrival to and departure from the helipad, the helicopter type, the helicopter registration tail number or N number, the operator, and the direction of flight to and from the helipad. For this noise measurement period, Table 2 provides the information from the UCSF helicopter transport logs. As indicated, all helicopter transport operations approximately followed the primary arrival and departure routes arriving from over the Bay and flying westerly to the UCSF helipad and departing from the UCSF helipad in an easterly direction towards the Bay. Figure 2 shows the actual radar flight tracks (acquired from San Francisco International Airport, SFO, noise monitoring system, ANOMS ) for the logged helicopter activity during the April-May, 2015 noise measurement period. Table 2. UCSF Log of Helicopter Transports Date Time of Time of Helicopter Approach Departure Tail # Operator Arrival Departure Type Direction Direction 4/23/ EC135 N838CS CALSTAR West East 4/25/ EC135 N834CS CALSTAR West East 4/26/ EC135 N838CS CALSTAR West East 4/27/ BELL 407 N43RX REACH West East 4/27/ EC135 N838CS CALSTAR West East 4/27/ EC135 N838CS CALSTAR West East 4/29/ EC135 N838CS CALSTAR West East 4/30/ EC135 N838CS CALSTAR West East 5/1/ EC135 N601MT MED TRANS West East Source: UCSF, May 2015; SFO ANOMS data, June UCSF HELICOPTER NOISE MEASUREMENT RESULTS For each helicopter transport HMMH determined the arrival and departure SENEL measured at the respective measurement sites using the approximate times provided in the UCSF log (Table 2). Since measurement Site H was on the hospital roof with a fairly steady background or ambient sound level environment (fans, air handlers, chillers, etc.) and closest to the helipad, HMMH determined that increases to the measured sound level at the recorded times of helicopter activity were indeed related to the helicopter operations. Since the other measurement sites were more exposed to community noise sources (street traffic, construction, etc.), the background or ambient sound levels varied and the helicopter operations were not as distinct. Therefore, HMMH used the times of the helicopter activity determined from the monitor at Site H to estimate a range of times when the helicopter would potentially be audible at the other sites. HMMH reviewed the collected data at the other sites to pinpoint the sound levels that would most likely be associated with the UCSF helicopter transport activity. In a few instances at some sites (especially Site D), there was little to no indication in the data that could be definitely associated with the helicopter transport operations due to already high ambient levels. In these cases, HMMH did not determine a SENEL for that respective helicopter transport operation for that particular site. Table 3 shows the various SENEL values at each measurement site for each helicopter arrival to and departure from the UCSF helipad. A * in the table for a specific helicopter transport operation indicates that a SENEL was not determined, as discussed above.

6 Page 6 Figure 2. Helicopter Radar Flight Tracks Source: SFO ANOMS

7 Page 7 Date Time of Arrival Time of Departure Table 3. Actual Measured Helicopter Single Event Noise Exposure Levels Helicopter Type Tail # SENEL (db) Site A Site C Site D Site E Site F Site H Arr Dep Arr Dep Arr Dep Arr Dep Arr Dep Arr Dep 4/23/ EC135 N838CS /25/ EC135 N834CS * /26/ EC135 N838CS /27/ BELL 407 N43RX * * /27/ EC135 N838CS * * /27/ EC135 N838CS * * * /29/ EC135 N838CS /30/ EC135 N838CS /1/ EC135 N601MT * * Range Maximum Note: * indicates helicopter activity not detected and SENEL not calculated. Source: UCSF, HMMH April - May 2015

8 Page 8 7. COMPARISON OF MEASURED SENEL WITH MODELED 95-dB SENEL CONTOUR The actual noise measurement program in April-May 2015 provided the following insight into the helicopter operation activity at the UCSF helipad: The dominant helicopter type operating to and from the UCSF helipad is the EC135 The sound levels measured from the single Bell 407 helicopter operation are within the range of the sound levels measured from the EC135 operations UCSF personnel indicated that operations by helicopter types other than theec135 will be rare Given these observations and information, HMMH used the FAA s INM program to model the EC135 and develop the predicted 95 db SENEL contour. The modeling was based on data developed for the SEIR and included EC135 arrival and departure profiles and the arrival and departure tracks. The modeling resulted in eight 95 db SENEL contours for the arrivals and departures which were then combined by overlaying the contours and drawing the outer or maximum extent of all contours. The result was a single 95 db SENEL contour representing all of the potential helicopter transport flight paths as provided in the SEIR and depicted in Figure 3. Figure 4 shows this predicted SENEL contour from modeling and the actual measured SENEL values (maximum and average) at each measurement site for comparison. As Figure 4 shows, the 95 db SENEL contour compares well to the noise measurements collected in April- May, 2015, except to the area adjacent to the Hospital campus to the south. The maximum SENEL measured at Site A was 89 db and is nearly on the 95 db SENEL contour, which implies the measured level is on the order of 6 db lower than modeled. The projected CNEL contour, which was developed using the FAA INM in the noise study for the SEIR, is also provided for reference. As previously discussed, the CNEL is the typical metric used to determine land use incompatibility and potential impact, but UCSF went beyond the normal standards and requirements by identifying the 95 db SENEL contour for use in addressing noise effects, particularly potential sleep awakenings, on the community. Figure 3. Primary, Secondary and Alternative Helicopter Flight Paths Source: UCSF

9 Page 9 Figure 4. Comparison of Actual Measurements and the Projected 95 db SENEL Contour Source: HMMH, FAA INM

10 Page DETERMINING THE EXTENT OF THE RSRP 95 db SENEL CONTOUR The modeling process using the FAA INM does not consider surrounding buildings or landscaping. As a result, the model does not calculate the effects of potential shielding and /or absorption of noise due to the blockage of direct line-of-sight between the source (helicopter) and the receiver. In Figure 4, Site A appears to be at or just outside of the modeled 95 db SENEL contour; however, the maximum SENEL actually measured at Site A was 89 db (at least a 6 db difference). The photograph for Site A in the appendix shows that potential shielding of this site from the helipad may be provided by the six-story hospital building across Mariposa St. from Site A. This shielding also was apparent during the measurements and observations associated with the helicopter operations in October To account for the noise shielding provided by the hospital, HMMH conducted a simplistic barrier analysis to determine a rough order magnitude of sound insertion loss from one side of the barrier (UCSF Medical Center building) to the other. In other words, the analysis was to determine the potential decrease in the sound level at Site A due to the south UCSF Medical Center building blocking the line-of-sight from Site A to the helicopter and helipad. Using data from the Geographic Information System (GIS) the estimated building elevations and distances from the sound source (helipad) and the barrier (UCSF Medical Center building) were determined and used in this analysis. The results indicated sound insertion loss or decrease of between 5 to 9 db from the source side of the barrier to the receiving site, Site A. Based on the measured sound level at Site H (maximum of 98 db) this would indicate that immediately beyond the barrier (UCSF property line along Mariposa St.) the projected SENEL would be less than 95 db SENEL. This analysis supported the actual measured sound level at Site A being approximately 6 db (for the maximum sound level of 89 db SENEL) less than the FAA INM projected sound level of approximately 95 db SENEL, which assumed no shielding of noise. Given this information, HMMH adjusted the 95 db SENEL contour such that it followed the edge of the hospital building along Mariposa St. except for the far west end of the building where there could potentially be some flanking or wrap-around sound from the southwest corner of the building. Figure 5 shows the resulting RSRP 95 db SENEL contour that includes the estimated noise shielding effects from the building. This effect is consistent with HMMH s findings in similar situations. Based on these results, UCSF has determined that there are no residential properties experiencing 95 db SENEL (interior level of 80 db) from normal UCSF helicopter transports. The UCSF accommodation of community concerns locating the helipad toward the center of campus and positioning the helipad elevator shaft to maximize noise reduction of helipad activities for the closest residential neighbors proved quite successful. In addition, the south UCSF Medical Center building helps to shield helipad noise from these neighbors. In accordance with the SEIR, all residential properties located on any block that is touched by the 95 db SENEL noise contour, whether or not the property lies within the contour, would be included in the RSRP. Thus, residential properties within the block defined by Mariposa and 18 th streets between Tennessee and Minnesota streets (see Figure 5) may apply for the RSRP. If, through additional testing, the sleeping areas are shown to experience SENEL greater than 80 db, those areas would qualify for sound reduction measures.

11 UCSF Helicopter Operations Measurements and Modeled SENEL in support of the RSRP Page 11 Figure 5. UCSF Residential Sound Reduction Program 95 db SENEL Contour Source: HMMH, FAA INM

12 UCSF Helicopter Operations Measurements and Modeled SENEL in support of the RSRP Page 12 Appendix A: Photographs of Measurement Sites Site A Site C

13 UCSF Helicopter Operations Measurements and Modeled SENEL in support of the RSRP Page 13 Site D Site E

14 UCSF Helicopter Operations Measurements and Modeled SENEL in support of the RSRP Page 14 Site F Site H

15 UCSF Helicopter Operations Measurements and Modeled SENEL in support of the RSRP Page 15 Appendix B: HMMH Profile HMMH is an international leader in environmental and capacity planning including noise and vibration control, air quality analysis, airport and airspace planning, and climate and energy solutions. With three offices throughout the country, we serve government and private industry clients with a broad range of innovative and effective solutions. What began in 1981 as a transportation noise consulting firm, HMMH provides a range of consulting services to clients related to aviation, highway, rail, transit, bus, industrial, construction, military, recreational, entertainment, and renewable energy projects. Our services encompass sophisticated simulation modeling to customized software tools to program planning and management. Strategic public communication is a key component of our offering; we excel at transforming complex technical issues into concepts that are easy to grasp. Aviation Noise HMMH provides expert assistance on the full spectrum of environmental and planning services to the aviation industry. HMMH s noise and vibration capabilities range from basic assessments of noise exposure to detailed, innovative technical analyses of unique aviation problems. HMMH is a leader in developing noise and land use compatibility plans under Title 14, Code of Federal Regulations (CFR) Part 150 and 161, in the design, specification, and installation of Noise and Operations Monitoring Systems (NOMS), in acoustical testing for sound insulation programs, and in conducting aircraft ground noise studies. The firm also tackles the tough challenges of Federal Environmental Assessments (EAs) and Environmental Impact Statements (EISs). In addition, HMMH provides comprehensive sound insulation solutions and ground-run-up enclosure designs. Helicopter Noise HMMH has helped airports, hospitals, TV stations, corporations, and even private individuals assess noise exposure from helicopter operations. Our services encompass everything from developing computer prediction models, to evaluating noise regulations, to conducting noise measurements in support of litigation. Our noise studies have been incorporated into environmental documentation for NEPA (National Environmental Policy Act) and CEQA (California Environmental Quality Act) requirements and our evaluations are routinely used in Title 14 CFR Part 150 Noise Compatibility Programs and similar airport noise studies. We are especially attuned to how helicopter noise impacts the public; we work closely with helicopter operators, airport/heliport/helipad owners, and the community to explain noise assessment methods and the impact of proposed actions.