11 ATTACHMENT 04 - Laserfiche WebLink

- 15 - Traffic and rail noise diminish at a rate of 3-6 dB for each doubling of the distance from the source to the receiver. Thus. other locations on the site at greater distances from the roadways or railroad will have lower noise levels. Additional acoustical shielding will be provided by interposed buildings of the project. B. Future Noise Levels Future traffic volume data for Stanley Boulevard were acquired from information contained the City of Pleasanton Noise Element. The Noise Element provides traffic volume data for many roadways throughout the City for year 2008 (time of the General Plan) and for future year 2025. The traffic volume for Stanley Bottles and is predicted to increase from the existing 7.800 ADT to 14,000 ADT for 2025. This increase in traffic volume yields a 3 dB increase in the traffic noise levels. C. Ground-Borne Vibration To determine the levels of railroad induced ground vibration. vibration level measurements were made at a location 70 ft. from the centerline of the railroad tracks. The measurements were made on March 13. 2009 using a PCB Piezotronics 393A03 accelerometer and a Larson Davis 2900 Dual Channel Real Time analyzer. The analyzer measured real time I%3-octave band vibration levels. in dB re: 1 x 10`' in./sec. for the three orthogonal directions over the frequency range of 0.8 to ]0 kHz. The vibration levels from 8 Hz to 80 Hz were used to assess the impact of ground borne vibration on homes of the project. Table IV on the following page provides the measured vibration levels for each type of train operation. TABLE IV Measured Ground Vibration Levels, VdB Freq.(Hz) 8 10 12.5 16 20 25 315 40 50 63 80 tOtAl. I i Freight 44.2 51.0 4 52.1 49.1 56.7 64.0 68.7 72.4 72.6 66.4 64.6 77.3 ACE 31.4 31 .7 38.4 42.5 47.4 52.9 61.7 67.1 66.6 57.0 51.4 70.8