Diablo Vista Pumping Plant Replacement Project. Noise and Vibration Analysis. East Bay Municipal Utility District

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1 Diablo Vista Pumping Plant Replacement Project Noise and Vibration Analysis East Bay Municipal Utility District October 2012

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3 Diablo Vista Pumping Plant Replacement Project Noise and Vibration Analysis East Bay Municipal Utility District October 2012

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5 Noise and Vibration Analysis Diablo Vista Pumping Plant Replacement Project TABLE OF CONTENTS 1. Introduction 1.1 Project Overview Environmental Setting Key Construction activities and Equipment Noise Levels Noise and Vibration Analysis 2.1 Noise Level Analysis by Construction Phase Pumping Plant Operational Noise Level Analysis Vibration Analysis by Construction Phase Noise and Vibration Mitigation Measures 3.1 Noise and Vibration Mitigation Measures Tables 1 New Diablo Vista Pumping Plant Construction Phase Activities Existing Diablo Vista Pumping Plant Demolition Phase Activities Existing Leland Rate Control Station Demolition Phase Activities New Diablo Vista Pumping Plant Construction Phase Noise Level Analysis... A-1 5 Existing Diablo Vista Pumping Plant Demolition Phase Noise Level Analysis... A-1 6 Existing Leland Rate Control Station Demolition Phase Noise Level Analysis... A-1 7 Projected Pumping Plant Operational Noise Level at nearest Sensitive Receptors...B-1 8 Projected Transformer Operational Noise Level at nearest Sensitive Receptors...B-1 9 Total Projected Operational Noise Level at nearest Sensitive Receptor...B-1 10 New Diablo Vista Pumping Plant Construction Phase Vibration Analysis...C-1 11 Existing Diablo Vista Pumping Plant Demolition Phase Vibration Analysis...C-1 12 Existing Leland Rate Control Station Demolition Phase Vibration Analysis...C-1 13 Peak Particle Velocity for Major Construction Equipment at 25 feet...c-1 14 Reaction to People and Damage to Buildings from Continous or Frequent Intermittent Vibration Levels...C-1 Figures 1 Existing and New Diablo Vista Pumping Plant Sites Project Sites Aerial View Project Site Locations

6 Noise and Vibration Analysis Diablo Vista Pumping Plant Replacement Project 4 City of Lafayette Projected Noise Contour Map with Diablo Vista Pumping Plant Site Areas and Nearest Sensitive Receptors to each Site... D-1 Appendices A B C D Noise Level Analysis by Construction Phase Pumping Plant Operational Noise Level Analysis Vibration Analysis by Construction Phase City of Lafayette Projected Noise Contour Map with Diablo Vista Pumping Plant Site Areas and Nearest Sensitive Receptors to each Site

7 Noise and Vibration Analysis Diablo Vista Pumping Plant Replacement Project CHAPTER 1 INTRODUCTION This report presents the results of the noise and vibration impact analysis for East Bay Municipal Utility District (EBMUD) s Diablo Vista Pumping Plant Replacement Project. Projected construction and operational noise levels at sensitive receptors near each of the three project site areas are analyzed. Sensitive receptors are defined as population groups more sensitive to noise that are associated with land uses such as residential areas, hospitals, schools, child care facilities, senior facilities, libraries, churches, and parks. The projected construction and operational noise levels at nearby sensitive receptors are compared against existing noise conditions. Potential construction related vibration impacts at structures near each project site area are also analyzed. Recommended mitigations to be implemented to reduce potential impacts to a less than significant level are also presented. 1.1 Project Overview The existing 12 million gallon per day (mgd) Diablo Vista Pumping will be replaced with a new 16 mgd pumping plant at the southwest corner of Mt. Diablo Boulevard and Mt. Diablo Court in the City of Lafayette. A transformer to provide power to the new pumping plant will be placed on the west side of the pumping plant structure. The existing Leland Rate Control Station will also be relocated to the new site as part of the project. Three new 30-inch water pipelines will connect the new pumping plant and rate control station to the existing water distribution system in Mt. Diablo Boulevard. Prior to the construction of the new pumping plant, the project will require the relocation of an existing 30-inch Reinforced Concrete Pipe (RCP) Storm Drain (SD) located at the new pumping plant project site. The 30-inch RCP SD will be replaced and relocated with approximately 240-feet of 24-inch High Density Polyethylene (HDPE) SD on the south side of Mt. Diablo Blvd and approximately 200 feet of 18-inch HDPE SD will be installed on the west side of Mt. Diablo Court. Upon construction completion and successful testing of the new facilities, the existing Diablo Vista Pumping Plant structure, located at 3305 Mt. Diablo Boulevard, Lafayette will be demolished. The existing Leland Rate Control Station vault, located on the north of Mt. Diablo Boulevard, approximately 850 feet west of Dolores Drive in the City of Lafayette will also be demolished. 1.2 Environmental Setting The new Diablo Vista Pumping Plant and new Leland Rate Control Station will be located on a 0.22 acre vacant parcel at the southwest corner of Mt. Diablo Boulevard and Mt. Diablo Court in the City of Lafayette. Highway 24 is located to the north of the parcel, the Lafayette Cemetery is located to the west, a commercial office building is 1-1

8 Noise and Vibration Analysis Diablo Vista Pumping Plant Replacement Project located to the east, and Blodgett s Abbey Carpet and Flooring is located to the south with 2 multi-family residential buildings south of the flooring store. The new pumping plant and rate control station will be constructed approximately 1,250 feet east of the existing pumping plant site as shown in Figure 1. The existing Diablo Vista Pumping Plant site, located on a 0.12 acre parcel at 3305 Mt. Diablo Boulevard in the City of Lafayette, is surrounded by commercial businesses. A hardware store is located to the west of the parcel and an automotive service shop is located to the east; south of the existing pumping plant property is a 2-story commercial building and parking area; and to the north is Mt. Diablo Boulevard and Highway 24. Source Google Maps/EBMUD Existing and New Diablo Vista Pumping Plant Sites Figure 1 The existing Leland Rate Control Station vault is located below grade under a portion of the parking/bike lane and sidewalk on the north side of Mt. Diablo Boulevard, approximately 850 feet west of Dolores Drive in the City of Lafayette. The access hatch structure to the underground vault is located on EBMUD property surrounded by open space. Approximately 100 feet east of the access hatch is a commercial office building. South of the personnel access hatch structure is Mt. Diablo Boulevard. Figure 2 shows an aerial view of the three project site areas. Figure 3 is a site map showing the three project site locations. 1-2

9 Noise and Vibration Analysis Diablo Vista Pumping Plant Replacement Project Source EBMUD Project Sites Aerial View Figure 2 Source EBMUD Project Site Locations Figure 3 1-3

10 Noise and Vibration Analysis Diablo Vista Pumping Plant Replacement Project 1.3 Key Construction Activities and Equipment Noise Levels Tables 1 through 3 provide a summary of key construction activities by project phase. Estimated durations, list of major equipment to be used along with associated reference equipment noise levels, and expected loudest construction noise level by activity are detailed in each project phase table. Summary of Key Construction Activities Table 1 - New Diablo Vista Pumping Plant Construction Phase Activities Estimated Duration (Weeks) 1 Major Construction Equipment & Reference Noise Levels 2 Loudest Noise Level Mobilization 1 Haul truck (84 dba), backhoe (80 dba) 84 Excavation/Site Work: *Clearing and grubbing *Excavate and remove onsite 30" RCP Storm Drain *Excavate and grade pumping plant pad, rate control station vault pad, and transformer pad HDPE Storm Drain Installations: *Installation of 24" HDPE Storm Drain on south side of Mt. Diablo Blvd *Installation of 18" HDPE Storm Drain in Mt. Diablo Ct. *Installation of two new Storm Drain Manholes and two new Drop Inlets. *Re-Pave Street after Storm Drain Installations Pumping Plant Construction (Concrete Work): *Construct Pumping Plant Foundation and Structure (i.e. walls, roof slab, etc.). *Construct Rate Control Station Vault *Construct Transformer Pad Pumping Plant Construction: *Roof construction, mechanical/electrical equipment installations, architectural elements Backfill: *Backfill around pumping plant Landscaping/Site Restoration: *Re-vegetation and planting *Site access and parking area pavement *Fence installation (dba 3 ) Crane (85 dba), excavator (85 dba), loader (80 dba), backhoe (80 dba), haul trucks (84 dba), chain saws (85 dba) 85 Crane (85 dba), excavator (85), loader (80 dba), backhoe (80 dba), haul trucks (84 dba), soil compactor (80 dba), roller (85 dba), asphalt paver (85 dba) 85 Crane (85 dba), concrete and shotcrete trucks (85 dba), excavator (85 dba), backhoe (80 dba), forklift (85 dba) 85 Crane (85 dba), excavator (85 dba), backhoe (80 dba), forklift (85 dba), material trucks (84 dba) Excavator (85 dba), loader (80 dba), soil compactor (80 dba), haul trucks (84 dba) Haul trucks (84 dba), backhoe (80 dba), soil compactor (80 dba), asphalt paver (85 dba), rollers (85 dba) Demobilization 1 Haul trucks (84 dba), backhoe (80 dba) 84 Total

11 Noise and Vibration Analysis Diablo Vista Pumping Plant Replacement Project Summary of Key Construction Activities Table 2 - Existing Diablo Vista Pumping Plant Demolition Phase Activities Estimated Duration (Weeks) 1 Remove/Demo Pumping Plant Equipment: *Removal of all plumbing, electrical and mechanical 1 components inside Pumping Plant Structure *Removal of Pumping Plant Roof Demolition of Pumping Plant Building/Foundation: *Demolition of structure and foundation 2 Removal and Demolition of Underground Piping: *Removal of all underground water pipelines and appurtenances to property line *Cap water pipelines at property line Backfill: -Backfill removed Pumping Plant structure foundation to existing grade -Backfill removed water pipeline trenches to existing grade Site Restoration: *Rough grade site to existing grade Total 1 6 Major Construction Equipment and Reference Noise Levels 2 Crane (85 dba), excavator (85 dba), haul trucks (84 dba) Excavator (85 dba), loader (80 dba), backhoe (80 dba), hoe ram (90 dba), concrete saw (90 dba) Excavator (85 dba), loader (80 dba), backhoe (80 dba) Excavator (85 dba), loader (80 dba), compactor (80 dba), haul trucks (84 dba) Soil compactor (80 dba), roller (85 dba), street sweeper (80 dba) Loudest Noise Level (dba 3 ) Summary of Key Construction Activities Table 3 - Existing Leland Rate Control Station Demolition Phase Activities Remove Equipment: *Remove/Demo concrete roof slab *Sidewalk and pavement removal *Remove internal vault components (24" valve, conical pipe sections, electrical conduits, ladder, etc.) Estimated Duration (Weeks) 1 1 Major Construction Equipment and Reference Noise Levels 2 Crane (85 dba), excavator (85 dba), backhoe (80 dba), concrete saw (90 dba) Loudest Noise Level (dba 3 ) 90 Demolition of Concrete Vault & Access Hatch: *Demo entire concrete vault and adjacent access hatch structure *Haul demolition material 1 Excavator (85 dba), backhoe (80 dba), hoe ram (90 dba), concrete saw (90 dba), haul trucks (84 dba) 90 Backfill: *Install pipe spool piece *Backfill with concrete or other backfill material *Backfill soil location where access vault was removed behind sidewalk Site Restoration: *Repave parking/bike lane *Restore Concrete Curb/Gutter and Sidewalk 1 1 Total 1 4 Crane (85 dba), haul truck (84 dba), concrete truck (85 dba), backhoe (80 dba), soil compactor (80 dba) 85 Soil compactor (80 dba), roller (85 dba), asphalt paver (85 dba), street sweeper (80 dba), backhoe (80 dba) 85 (1) Estimated duration does not include down time, mobilization/demobilization between project phases, submittal review, equipment/material procurement, pumping plant startup/testing, etc. nor reflect total duration. (2) Reference Noise Levels, shown in parentheses for each major piece of onsite construction equipment, are from the U.S. Department of Transportation - Federal Highway Administration: 2006 Typical Construction Equipment Reference Noise Levels. (3) dba, A-Weighted Sound Level: Sound pressure level in decibels measured on a sound level meter using A-weighting filter network. The A-weighting filter de-emphasizes the very low and very high frequency components of sound in a manner similar to the frequency of the human ear and correlates well with subjective reactions to noise 1-5

12 CHAPTER 2 NOISE AND VIBRATION ANALYSIS Noise and Vibration Analysis Diablo Vista Pumping Plant Replacement Project 2.1 Noise Level Analysis by Construction Phase The 2002 City of Lafayette General Plan produced a Projected Noise Contour Map with projected average day/night noise levels (dba L dn ) throughout the City of Lafayette. Based on the Noise Contour Map, the current average noise level at all project site areas are approximately 75 dba. The 75 dba sound level at each project site is reflective of each site s close proximity to Highway 24 and Mt. Diablo Boulevard. EBMUD s projected construction noise level analysis was conducted to determine the expected noise level at the nearest sensitive receptors to each project site during the loudest construction activity for each phase. Construction equipment reference noise levels for each project phase activity are detailed in Tables 1 through 3. The loudest projected noise levels at the nearest sensitive receptors would be 71 dba, 74 dba, and 68 dba for the new pumping plant construction, existing pumping plant demolition, and existing rate control station demolition phases. Based on the City of Lafayette s Noise Contour Map, the average noise levels at these sensitive receptor locations currently varies between dba. Noise levels diminish (attenuates) as the distance from a noise source increases. Other mitigating factors for noise attenuation are the presence of trees, vegetation, topography, and structures which would shield many receptors from direct line-of-sight noise transmission from specific construction activities, particularly receptors at lower elevations than the project sites. The construction phase noise level analysis conducted is a conservative approach as it does not take into account attenuation factors related to vegetation, topography, and structural obstructions between each project site and the nearest sensitive receptors to each site. Actual noise levels at sensitive receptors would likely be lower than estimated above, as actual attenuation would be greater than assumed. The project s short term exposure of persons to demolition and construction noise levels are therefore estimated to fall within the City of Lafayette s existing sounds levels at nearby sensitive receptors. Therefore, the project s impact related to a substantial temporary or periodic increase in ambient noise levels in the project vicinity above levels existing without the project would be less than significant. Although EBMUD is not subject to local jurisdiction zoning ordinances for projects involving the transmission of water (Government Code section 53091), EBMUD strives to consider local noise ordinances during construction, where feasible and not contrary to its public purpose and responsibilities. By limiting work hours and implementing best management construction practices, noise resulting from the project is considered less than significant. Mitigation measures limiting planned construction work hours during the daytime, limiting the possibility of annoyance during typical periods of sleep or rest 2-1

13 Noise and Vibration Analysis Diablo Vista Pumping Plant Replacement Project are identified in Mitigation Measure NOI-1 in Section 3.1. Best Management Practices (BMPs) related to Noise Control and Noise Complaint Procedures are identified in Mitigation Measure NOI-2 and NOI-3 in Section 3.1, respectively. The projected noise levels at the nearest sensitive receptors by construction phase are detailed in Tables 4 through 6 in Appendix A. The City of Lafayette Projected Noise Contour Map with the Diablo Vista Pumping Plant Project site areas and nearest sensitive receptors to each site is shown in Figure 4 in Appendix D. 2.2 Pumping Plant & Transformer Operational Noise Level Analysis EBMUD s projected operational noise level analysis was conducted to determine the expected new pumping plant and transformer noise level at the nearest sensitive receptors to the new pumping plant site. The combined total pumping plant and transformer projected operational noise level at the nearest sensitive receptors will vary between dba. Based on the City of Lafayette s Noise Contour Map, shown in Appendix D, the average noise levels at these sensitive receptor locations currently varies between dba. The operational noise level analysis conducted is a conservative approach, similar to the construction phase noise level analysis, as it does not take into account attenuation factors related to vegetation, topography, and structural obstructions between the new pumping plant project site and the nearest sensitive receptors to the site. Actual noise levels at sensitive receptors would likely be lower than estimated above, as actual attenuation would be greater than assumed. The project s permanent operational noise level is therefore estimated to fall below the City of Lafayette s existing sound levels at nearby sensitive receptors. Therefore, there would be no impact related to a substantial permanent increase in ambient noise levels in the project vicinity above levels existing without the project. The projected operational noise levels at the nearest sensitive receptors to the new pumping plant site are detailed in Tables 7 through 9 in Appendix B. 2-2

14 2.3 Vibration Analysis by Construction Phase Noise and Vibration Analysis Diablo Vista Pumping Plant Replacement Project The California Department of Transportation uses a vibration limit 0.5 inches per second (in/sec) peak particle velocity (PPV) for buildings designed to modern engineering standards. EBMUD has successfully applied the 0.5 in/sec standard criteria established to evaluate the risk for cosmetic or structural damage to buildings with no known adverse impacts. The new pumping plant construction, water pipeline installation, and existing rate control station demolition project phases would not result in exposure of persons to or generation of excessive ground-borne vibration levels. Each of the above construction phases are at locations far enough away from any nearby structures to not approach the 0.5 in/sec PPV. The auto body shop building east of the existing Diablo Vista Pumping Plant structure is approximately 25 feet away. The hardware store building west of the existing pumping plant building is also approximately 25 feet away. PPV values at 25 feet would not exceed 0.21 in/sec. The demolition, back-filling, grading and compacting at the existing pumping plant site would occur at distances less than 25 feet from the nearby buildings. Equipment anticipated during project demolition includes: backhoes, excavators, cranes, dump trucks, front end loaders, concrete saw, hoe ram, vibratory compactor, water trucks, asphalt pavers, and various passenger vehicles. To not exceed the 0.5 in/sec PPV during the existing Diablo Vista Pumping Plant demolition phase work, implementation of Mitigation Measure NOI-4 in Section 3.1 will lessen potential impacts to a less than significant level. While BMPs related to construction practices will limit vibrations and damage to adjacent structures is not anticipated, preconstruction building surveys will be offered and conducted if approved by nearby property owners to ensure that structures are maintained at their pre-construction condition (Mitigation Measure NOI-4 in Section 3.1). Two monitoring stations for project vibration level measurements will also be placed on the east and west sides of the existing Diablo Vista Pumping Plant site. Communication with the measurement system, including daily reports would be prepared. Vibration will be limited to no more than 0.5 in/sec PPV. The vibration analysis by construction phase is detailed in Tables 10 through 12 in Appendix C. Table 13 lists PPV values for major construction equipment and Table 14 lists the reaction of people and the potential damage to buildings at various vibration PPV levels. Table 13 and 14 are also in Appendix C. 2-3

15 Noise and Vibration Analysis Diablo Vista Pumping Plant Replacement Project CHAPTER 3 NOISE AND VIBRATION MITIGATION MEASURES 3.1 Noise and Vibration Mitigation Measures Mitigation Measure NOI-1: Day and Hours of Construction Operations a) Construction activities will be limited to between 8:00 a.m. and 8:00 p.m. Monday through Friday. Trucks and personnel can arrive at the site for reporting, minor tasks, and meetings after 7:00 a.m. but no construction work that would be audible off-site by residents nearby can begin until 8:00 a.m. b) Extreme noise generating activities greater than 90 dba at 50 feet will be limited to between 8:00 a.m. and 4:00 p.m. Monday through Friday. c) Any construction activity proposed outside of the standard hours of 8:00 a.m. to 8:00 p.m. (Monday through Friday), with the exception for emergencies, must be approved by EBMUD. EBMUD will also notify residents and businesses along Mt. Diablo Boulevard and Mt. Diablo Court by postcard. d) No extreme noise-generating activities would be allowed on Saturdays. e) No construction activity would take place on Sunday or Federal holidays. f) For clarification, construction activities include but are not limited to: truck idling, all moving equipment (including trucks, excavators, etc), stationary noise generating equipment such as generators or materials, deliveries, and construction meetings held on-site in a non-enclosed area. Mitigation Measure NOI-2. Noise Control a) Equipment and trucks used for project construction would utilize the best available noise control techniques (e.g., improved mufflers, equipment redesign, use of intake silencers, ducts, engine enclosures and acoustically-attenuating shields or shrouds, wherever feasible). b) Impact tools (e.g., jack hammers, pavement breakers, and rock drills) used for project construction would be hydraulically or electrically powered wherever possible to avoid noise associated with compressed air exhaust from pneumatically powered tools. However, where use of pneumatic tools is unavoidable, an exhaust muffler on the compressed air exhaust would be used; this muffler can lower noise levels from the exhaust by up to about 10 dba. External jackets on the tools themselves would be used where feasible, and this could achieve a reduction of 5 dba. Quieter procedures would be used, such as drills rather than impact equipment, whenever feasible. 3-1

16 Noise and Vibration Analysis Diablo Vista Pumping Plant Replacement Project c) Stationary noise sources would be located as far from adjacent residential or sensitive receptors as possible, and they would be muffled and enclosed within temporary sheds, incorporate insulation barriers, or other measures to the extent feasible. d) If feasible, the noisiest phases of construction (such as pavement saw cutting) will be limited to less than 10 days at a time. Mitigation Measure NOI-3. Noise Complaint Procedures a) Contractor would provide a procedure and phone numbers for notifying the EBMUD staff (during regular construction hours and off-hours); b) Install a sign posted on-site with permitted construction days and hours, and who to notify in the event of a problem; c) Notification of neighbors and occupants within 300 feet of the project construction area at least 30 days in advance of pile-driving activities and the estimated duration of the activity; and d) A preconstruction meeting would be held with EBMUD inspectors and the general contractor/on-site project manager to confirm that noise mitigation and practices (including construction hours, noise control, neighborhood notification, posted signs, etc.) are in place or completed. Mitigation Measure NOI-4. Vibration Control To prevent cosmetic or structural damage to adjacent or nearby structures, EBMUD will incorporate into contract specifications restrictions on equipment operation, whereby surface vibration will be limited to no more than 0.5 in/sec PPV, measured at the nearest structures. If vibration levels are found to exceed the 0.5 in/sec PPV threshold, construction will be halted immediately and alternative construction methods will be implemented to maintain vibration levels below this threshold. Preconstruction building surveys will be offered and conducted if approved by nearby property owners to ensure that structures are maintained at their preconstruction condition. Any new cracks or other changes in structures will be compared to preconstruction conditions and a determination made as to whether the proposed project could have caused such damage. In the event that the project is demonstrated to have caused the damage, EBMUD will have the damage repaired to the pre-existing condition. 3-2

17 Appendix A

18 Diablo Vista Pumping Plant Replacement Project - Noise Level Analysis by Construction Phase Table 4 - New Diablo Vista Pumping Plant Construction Phase Noise Level Analysis (Site Elevation = 310 ft) Sensitive Receptor 4 Projected Noise Level at nearest Sensitive Receptor during Key Construction Activities (dba) Receptor (Type) Construction Site to Distance Excavation & HDPE Storm Pumping Plant Pumping Plant Landscaping & Elev Sensitive Receptor Adjustment Mobilization Backfill Demobilization Site Work Drain Installation Concrete Work Construction Site Restoration (ft) Distance (ft) (dba) (84 dba) 5 (85 dba) 5 (85 dba) 5 (85 dba) 5 (85 dba) 5 (85 dba) 5 (85 dba) 5 (84 dba) 4 Lafayette Pointe Condos (Residential) Lafayette Commons Apartments (Residential) Lafayette Highlands Apartments (Residential) Lafayette Park Hotel & Spa (Hotel) Table 5 - Existing Diablo Vista Pumping Plant Demolition Phase Noise Level Analysis (Site Elevation = 305 ft) Sensitive Receptor 4 Projected Noise Level at nearest Sensitive Receptor during Key Construction Activities (dba) Receptor (Type) Elev (ft) Construction Site to Sensitive Receptor Distance (ft) Distance Adjustment (dba) Remove Equipment (85 dba) 5 Demo Building & Foundation (90 dba) 5 Demo/Remove Underground Piping (85 dba) 5 Backfill Site Restoration (85 dba) 5 (85 dba) 5 Lafayette Highlands Apartments (Residential) Residential Homes off of Carol Lane (Residential) Lafayette Park Hotel & Spa (Hotel) Lafayette Pointe Condos (Residential) Table 6 - Existing Leland Rate Control Station Demolition Phase Noise Level Analysis (Site Elevation = 340 ft) Sensitive Receptor 4 Projected Noise Level at nearest Sensitive Receptor during Key Construction Activities (dba) Receptor (Type) Elev Construction Site to Sensitive Receptor Distance (ft) Distance Adjustment (dba) Remove Equipment (90 dba) 5 Demo Vault and Access Hatch Structure (90 dba) 5 Backfill (85 dba) 5 Site Restoration (85 dba) 5 Residential Homes off of West Road (Residential) 325 Temple Isaiah (Church) (4) Sensitive Receptors: Are land uses regarded as being more sensitive to noise due to types of population groups (children, elderly) or activities involved and include residential areas, hospitals, schools, child care facilities, senior facilities, libraries, churches, and parks. (5) = Loudest projected construction equipment noise level at 50 feet for each construction activity. Major construction equipment noise level values listed in Tables 1-3. The maximum projected construction noise levels at the nearest sensitive receptors would be approximatley 71 dba, 74 dba, and 68 dba for the new pumping plant construction, existing pumping plant demolition, and existing rate control station demolition phases. Based on the City of Lafayette's Projected Noise Contour Map (see Figure 5 in Appendix D) the average day/night noise levels at these sensitive receptor locations currently varies between dba. The project's short term exposure of persons to demolition and construction noise levels are therefore estimated to fall within the City of Lafayette's existing sounds levels at nearby sensitive receptors. Note on Construction Noise Analysis Noise levels diminish (attenuates) as the distance from a noise source increases. Other mitigating factors for noise attenuation is the presence of trees, vegetation, topography, and structures which would shield many receptors from direct line-of-sight noise transmission from specific construction activities, particularly receptors at lower elevations than the project sites. The above analysis is a conservative approach as it does not take into account attenuation factors related to vegetation, topography, and structural obstructions between each project site and the nearest sensitive receptors to each site. Actual noise levels at sensitive receptors would likely be lower than estimated above, as actual attenuation would be greater than assumed. A-1 ]

19 Appendix B

20 Diablo Vista Pumping Plant Replacement Project - Pumping Plant Operational Noise Level Analysis Table 7 - Projected Pumping Plant Operational Noise Level at nearest Sensitive Receptors Enclosure Reduction Pumping Plant Ref Hourly L eq Distance between Facility and Distance Adjustment Adjusted L eq Projected Pumping Plant Noise Level Drop Sensitive Receptor in 50 feet 6 Sensitive Receptor (ft) (dba) (dba) (dba) 6 & 7 L eq (dba) Lafayette Pointe Condos (Residential) Lafayette Commons Apartments (Residential) Lafayette Highlands Apartments (Residential) Lafayette Park Hotel & Spa (Hotel) (6) East Bay Municipal Utility District, 2006 Water Treatment & Transmission Improvements Program - Pumping Plants Noise Analysis (7) Assumes Pumping Plant Building Louvers are on the north and south sides of building. East and west walls of building would have no Louvers. Louvered enclosures that block noise but allow for air circulation would reduce noise levels by 20 dba (North and south sides of building). Non Louvered sides of building (East and west walls) would reduce noise levels by 40 dba. Table 8 - Projected Transformer Operational Noise Level at nearest Sensitive Receptors Sensitive Receptor Transformer Ref Hourly L eq in 50 feet 8 Distance between Facility and Sensitive Receptor (ft) Distance Adjustment (dba) Adjusted L eq (dba) Transformer Enclosure Noise Reduction (dba) 9 Projected Transformer L eq (dba) Lafayette Pointe Condos (Residential) Lafayette Commons Apartments (Residential) Lafayette Highlands Apartments (Residential) Lafayette Park Hotel & Spa (Hotel) (8) East Bay Municipal Utility District, 2012 Estimated Sound Level for a 1500kVA Transformer (65 dba at 1-foot) (9) East Bay Municipal Utility District, 2006 Estimated Transformer Enclosure Noise Reduction. Table 9 - Total Projected Operational Noise Level at nearest Sensitive Receptor Sensitive Receptor Projected Pumping Plant L eq (dba) Projected Transformer L eq (dba) Lafayette Pointe Condos (Residential) 39 7 Lafayette Commons Apartments (Residential) 36 4 Lafayette Highlands Apartments (Residential) 34 2 Lafayette Park Hotel & Spa (Hotel) 10 0 (10) Source: 2002 City of Lafayette General Plan, Map VII-1 Projected Noise Contours (see Figure 1) Total Projected Operational L eq (dba) Average Day/Night Noise Level, L dn City of Lafayette 10 (dba) Equivalent Noise Level (Leq) - The average A-weighted noise level during a measurement period. L dn : The average A-weighted noise level during a 24-hour day, obtainined after additional 10 decibels to levels measured in the night between 10:00 PM and 7:00 AM. B-1

21 Appendix C

22 Diablo Vista Pumping Plant Replacement Project - Vibration Analysis by Construction Phase Nearest Structure Blodgetts Abbey Carpet & Flooring Distance to Project Site (ft) Table 10 - New Diablo Vista Pumping Plant Construction Phase Vibration Analysis Projected Peak Particle Velocity [PPV (in/sec)] Vibration Level at nearest Structure during Key Construction Activities Mobilization (Haul truck) 11 Excavation & Site Work (Excavator) 11 HDPE Storm Drain Installation (Roller) 11 Pumping Plant Concrete Work (Excavator) 11 Pumping Plant Construction (Excavator) 11 Backfill (Compactor) 11 Landscaping & Site Restoration (Roller) 11 Demobilization (Haul truck) Nearest Structure Table 11 - Existing Diablo Vista Pumping Plant Demolition Phase Vibration Analysis Projected PPV (in/sec) Vibration Level at nearest Structures during Key Construction Distance from Existing Pumping Plant Structure (ft) Remove Equipment (Excavator) 11 Demo Building & Foundation (Hoe Ram) 11 Demolition/Remove Underground Piping (Excavator) 11 Backfill (Compactor) 11 Site Restoration (Roller) 11 Svensson Automotive Ace Hardware Table 12 - Existing Leland Rate Control Station Demolition Phase Vibration Analysis Projected PPV (in/sec) Vibration Level at nearest Structure during Key Construction Activities Distance from Nearest Remove Existing Rate Control Demolition Vault and Access Hatch Structure Backfill Site Restoration Structure Equipment Station (ft) (Excavator) 11 (Hoe Ram) 11 (Compactor) 11 (Roller) 11 Office Building (11) Construction Equipment with highest Peak Particle Velocity [PPV (in/sec)] Vibration Level at 25 feet to be used during each specific construction activity. PPV values listed in Table 13. Table 13 - Peak Particle Velocity (PPV) for Major Construction Equipment at 25 feet 12 Equipment Haul Trucks Excavator Hoe Ram Compactor Roller PPV (in/sec) (12) 2006 Federal Transit Authority, Transit Noise and Vibration Impact Assessment Table 14 - Reaction of People and Damage to Buildings From Continuous or Frequent Intermittent Vibration Levels 13 Vibration Level, PPV (in/sec) Human Reaction Effects on Buildings 0.01 Barley perceptible No effect 0.01 Distinctly perceptible Vibration unlikely to cause damage of any type to any structure 0.08 Distinctly to strongly perceptible Recommended upper level of the vibration to which ruins and ancient monuments should be subjected 0.10 Strongly perceptible Virtually no risk of damage to normal buildings 0.30 Strongly to Severe perceptible Threshold at which there is a risk of damage to older residential dwellings such as plastered walls or ceilings 0.50 Severe - Vibrations unpleasant Threshold at which there is a risk of damage to newer residential structures (13) 2004 California Department of Transportation, Transportation and Construction Induced Guidance Manual EBMUD has successfully applied the 0.5 in/sec standard criteria established to evaluate the risk for cosmetic or structural damage to buildings with no known adverse impacts. The new pumping plant construction, water pipeline installation, and existing rate control station demolition project phases are at locations far enough away from any nearby structures to not approach the 0.5 in/sec PPV. An auto body shop building east of the existing Diablo Vista Pumping Plant structure is approximately 25 feet away. A hardware store building west of the existing pumping plant building is also approximately 25 feet away. PPV values at 25 feet would not exceed 0.21 in/sec. The demolition, back-filling, grading, and compacting at the existing pumping plant site would occur at distances less than 25 feet from the nearby buildings. To not exceed the 0.5 in/sec PPV during the pumping plant demolition phase work, the following mitigations are recommended: a) Surface vibration will be limited to no more than 0.5 in/sec PPV, measured at the nearest structures. If vibration levels are found to exceed the 0.5 in/sec PPV threshold, construction will be halted immediately and alternative construction methods will be implemented to maintain vibration levels below this threshold. b) At the request of and with permission of building owners, EBMUD will conduct a preconstruction survey of adjacent structures for potential effects due to vibration-generating activities. Any new cracks or other changes in structures will be compared to preconstruction conditions and a determination made as to whether the proposed project could have caused such damage. In the event that the project is demonstrated to have caused the damage, the District will have the damage repaired to the pre-existing condition. W:\WSP\Oscar\Projects\Diablo Vista PP\MND Analysis\MND Sections\12 - Noise\ Krista_OH_Noise\ DVPP_Vibration Analysis.xls C-1

23 Appendix D

24 Moraga Rd Springhill Rd. Reliez Vall ey Rd. Pleasant Hill Rd. El Nido Ranch Rd. Acalanes Rd. 24 Upper Happy Valley Rd. 60 LAFAYETTE RESERVOIR Happy Valley Rd. Mt. Diablo Blvd Oak Hill Rd Hamlin Rd School St. Deer Hill Rd. Moraga Blvd. 60 Carol Ln. St. Mary's Rd. Glenside Dr. 24 Olympic Blvd Reliez Station Rd. Stanley Blvd Glenside Dr. Burton Dr. 55 St. Mary's Rd. Silverado Dr. Merriewood Rohrer Dr Feet for schematic purposes only Legend 60 Noise contour in decibels (dba Ldn) City Limits Reservoir Map VII-1 Projected Noise Contours City of Lafayette General Plan Source: City of Lafayette, 1998