3_Exhibit B - Laserfiche WebLink

Ramboll - Stoneridge Mall Residential Project 158850326.2 7/11 Confidential the average non-peak hourly traffic to represent nighttime traffic. In addition, it was assumed that the percentages of truck traffic are the same for both day and night. The results are summarized in Table 4. Table 4. Traffic Sound Levels at Outdoor Activity Areas Outdoor Activity Location Predicted Ldn (dBA) Central Courtyard 53 Western Courtyard 54 Central Rooftop Deck on Level 5 65 Northeast Rooftop Deck on Level 4 71 As shown in Table 4, the limit of 65 dBA Ldn is exceeded for the northeast rooftop deck. The primary sources of noise are I-580 and I-680. Additional Measure To reduce the traffic noise to an Ldn sound level at or below 65 dBA Ldn at the northeast rooftop deck on Level 4, a rooftop barrier is recommended to shield the northeast rooftop deck from traffic noise. The barriers should run the length of the east and north edges of the rooftop deck, be at least 6 feet high, have a minimum surface weight of 3 psf, and have no cracks or gaps. Glass or another transparent material can be used. With the barrier in place, the results of the model show a sound level 65 dBA Ldn at the northeast rooftop deck Level 4. 4. Assessment of Noise from Stationary (Non-transportation) Sources in the Vicinity of the Project (MM 4.J-6a) Pursuant to the referenced SEIR, specifically the prescribed Mitigation Monitoring and Reporting Program, the following is a condition of approval for the subject project. MM 4.J-6a – For all of the potential sites for rezoning the City shall require site-specific acoustical assessments to determine noise exposure, impact, and mitigation regarding non- transportation sources. Noise exposure shall be mitigated to satisfy the applicable City Code criterion using appropriate housing site design. The SEIR addresses the impact of off-site activities on the rezoning sites, noting that this measure was imposed in part because “some [rezoning sites] adjacent to industrial/commercial areas could be subject to loading noise and late or 24-hour operations noise.” The SEIR states: The City of Pleasanton Municipal Code limits noise exposure from stationary/non- transportation sources to 60 dB Lmax at any point outside of the property plane, unless otherwise specified in the Municipal Code (Section 9.04.030). Sources of noise that do not produce noise exposure in excess of 70 dB Lmax/Leq at a distance of 25 feet are exempt from this criterion between the hours of 8:00 a.m. and 8:00 p.m. Monday through Friday (except holidays) and 10:00 a.m. and 6:00 p.m. on Sundays and holidays.