Noise and Vibration Assessment

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Daily 7 a.m. to 7 p.m.Weekends 9 a.m. to 8 p.m.Short-Term OperationResidential 80 65Commercial, Industrial 85 70Long-Term OperationResidential 65 55Commercial, Industrial 70 602. The nighttime noise level received by any land use and produced by any construction ordemolition activity between weekday hours of seven (7) p.m. and seven (7) a.m. or betweeneight (8) p.m. and nine (9) a.m. on weekends and federal holidays shall not exceed theapplicable nighttime noise level standards outlined in this section.Maximum instantaneous noise levels resulting from the noisiest construction activities proposed forthe project (i.e., jack hammering) would be approximately 89 dBA L max at 50 feet. Maximuminstantaneous noise levels from other required equipment would typically be less than 85 dBA L maxat 50 feet. Maximum noise levels are calculated to exceed the City of Berkeley Community NoiseOrdinance limit of 60 dBA L max for long-term operations (period of 10 days or more) whenmaximum noise events occur within 1,400 feet of sensitive land uses with direct line of sight to theseactivities. Maximum noise levels would potentially violate the Berkeley Community NoiseOrdinance limits over a period ranging from 35 to 47 days.Maximum noise levels would exceed the City of Oakland’s Planning Code limit of 65 dBA L max forlong-term operations (period of 10 days or more) when maximum noise events occur within 800 feetof sensitive land uses having direct line of sight to the work area. Maximum noise levels wouldpotentially violate the Oakland’s Planning Code limit over a period ranging from 20 to 26 days.Construction noise resulting from the project would be mitigated by limiting activities to theallowable hours established by the City of Berkeley and City of Oakland and by implementing bestmanagement construction practices as discussed under Impact d). By following the bestmanagement construction practices discussed under Impact d), the impact would be reduced to a lessthan significant level.Impact b)Less than Significant Impact. The project would not result in exposure of persons toor generation of excessive ground-borne vibration levels.There are no local, state, or federal vibration impact criteria that are applicable to this project. TheCalifornia Department of Transportation uses a vibration limit of 12.7 mm/sec (0.5 in/sec), PPV forbuildings structurally sound and designed to modern engineering standards. A conservative vibrationlimit of 5 mm/sec (0.2 in/sec), PPV has been used for buildings that are found to be structurallysound but structural damage is a major concern. For historic buildings or buildings that aredocumented to be structurally weakened, a conservative limit of 2 mm/sec (0.08 in/sec), PPV is often11
used to provide the highest level of protection. All of these limits have been used successfully, andcompliance to these limits has not been known to result in appreciable structural damage. Allvibration limits referred to herein apply on the ground level and take into account the response ofstructural elements (i.e. walls and floors) to ground-borne excitation.The majority of project construction activities would employ open-trench construction methods toinstall the new backbone pipeline, distribution lines, cross-connections, and customer serviceconnections. After the pipelines are installed, the trench and pavement would be restored. Finally,the existing pipelines and connections would be abandoned.Activities with the potential of generating perceptible vibration levels would include the removal ofpavement and soil, shoring, and the compacting of backfill after the new pipeline is installed. Theproposed project would, at times, bring construction activities within about 25 feet of sensitive landuses along the project alignment. Table 6 summarizes typical vibration levels associated withvarying pieces of construction equipment at a distance of 25 feet.Equipment anticipated during project construction would include: backhoes, excavators, cranes,dump trucks, front end loaders, asphalt pavement grinders, boiler trucks, bypass pipes, asphaltpavers, concrete trucks and various passenger vehicles. Neither vibratory or impact pile driving areproposed as part of the construction of the project.A review of the proposed equipment and the vibration level data provided in Table 5 indicates thatvibration levels generated by the majority of proposed equipment would be equal to or below the 0.2in/sec PPV criteria used to assess the potential for cosmetic damage to buildings of normalconventional construction. Vibration levels from dropping heavy equipment (clam shovel drop) orthe operation of a vibratory roller at a distance of 25 feet could slightly exceed the 0.2 in/sec PPVcriteria. Theoretically, these potential exceedances could be up to one one-hundredth of an inch persecond PPV (0.01 in/sec PPV). However, at a distance of 26 feet, the levels are calculated to be lessthan the 0.2 in/sec PPV criteria. Sporadic events such as dropping of heavy objects, and the use ofvibratory rollers within 25 feet of residences should be avoided to the extent possible. The impactresulting from the project would be considered less-than-significant as vibration levels would notexceed the 0.2 in/sec PPV criteria established to evaluate the risk for cosmetic or structural damageto buildings. Vibration levels generated by construction activities would be perceptible indoors andmay be considered annoying. However, planned construction hours are during the daytime, limitingthe possibility of annoyance during typical periods of sleep or rest, and would only affect a particularresidence for a brief period of time as construction activities occur in areas immediately adjoining theresidence.12
Page 1 and 2: DINGEE BACKBONE PIPELINE REPLACEMEN
Page 3 and 4: noise at any instant in time, commu
Page 5 and 6: Table 1Definitions of Acoustical Te
Page 7 and 8: Table 3 Reaction of People and Dama
Page 9 and 10: at “slow” response. The sound l
Page 11: Mobile Equipment. Maximum sound lev
Page 15 and 16: Table 7Typical Range of Noise Level
Page 17 and 18: Major Project Cases:a) Such activit
Page 19: construction activities would be of

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