Draft Environmental Impact Report - California Off Highway Vehicle ...

3.3 Noise
Construction of new facilities and operation of Clay Pit SVRA (e.g., maintenance activities and
increased use of OHVs) have the potential to result in varying degrees of temporary ground
vibration, depending on the specific equipment used and operations involved. Vibration spreads
through the ground and diminishes in magnitude with increases in distance. Table 3.3‐4 displays
vibration levels for typical construction and maintenance equipment; vibration produced by OHVs
would be substantially less.
TABLE 3.3­4. TYPICAL VIBRATION LEVELS CAUSED BY CONSTRUCTION AND
MAINTENANCE EQUIPMENT
Equipment PPV at 25 feet (in/sec) Approximate Lv at 25 feet 1
Large bulldozer 0.089 87
Trucks 0.076 86
Jackhammer 0.035 79
Small bulldozer 0.003 58
Notes: in/sec = inches per second; PPV = peak particle velocity.
1 Where Lv is the velocity level in decibels and based on the root mean square velocity amplitude.
Source: FTA 2006:12‐12
Vibration levels generated during construction and maintenance would fluctuate depending on
the specific location of activities in Clay Pit SVRA and on the particular type, number, and duration
of use of various pieces of construction and maintenance equipment. Equipment required for
construction and maintenance activities could include concrete mixer/pump trucks, graders,
pneumatic tools, and various other trucks. The most intense generation of ground vibration would
be associated with bulldozers that generate levels of 0.089 in/sec PPV and 87 VdB at a distance of
25 feet. These levels would attenuate to 0.0052 in/sec PPV and 62 VdB at a distance of 165 feet
(i.e., the distance to the closest sensitive receptor to construction activities) (Appendix D). Because
these levels would not exceed Caltrans’ or FTA’s standards of 0.2 in/sec PPV and 80VdB
respectively, these temporary and short‐term vibration impacts would be a less­than­significant
impact.
Mitigation Measures: No mitigation is required.
IMPACT
3.3-4
Increase in Temporary Short-Term Off-Site Noise Levels during Construction and Maintenance
Construction and maintenance activities associated with the construction of facilities envisioned
in the Clay Pit SVRA General Plan would generate short‐term, temporary, and intermittent noise at
or near individual noise‐sensitive locations in the project area. Noise levels generated during
construction and maintenance would fluctuate depending on the physical location of construction
activities at the SVRA, and on the particular type, number, and duration of use of various pieces of
Clay Pit State Vehicular Recreation Area
February 2012 3.3-20 Draft EIR