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

3.2 Air Quality
commonly contain volatile organic compounds and may contain toxic air contaminants (TACs) and
greenhouse gases.
Existing Criteria Pollutant Emissions
Existing facilities at Clay Pit SVRA include a 0.6‐acre paved parking lot, two shade ramadas, two
picnic tables, one vault toilet, and one interpretive sign. The SVRA is open for day use only, and
OHV activities take place throughout the SVRA. This is the context in which baseline local
emissions are generated.
Area Sources
Area sources of emissions at the SVRA are measurably negligible, with the exception of PM10
which is generated as windblown fugitive dust from loose soils throughout the SVRA. Windblown
fugitive dust levels vary throughout each day depending on weather conditions.
Mobile Sources
Mobile source emissions at Clay Pit SVRA come from vehicles traveling to and from the SVRA and
from OHVs being driven at the SVRA. Based on traffic counts taken at Clay Pit SVRA in April 2010,
during a peak weekend day, the SVRA generates 124 vehicle trips, and approximately 93 OHVs
operate at the SVRA (Appendix C in the Clay Pit SVRA General Plan and Appendix B in this DEIR).
Also, most visitors are estimated to reside within 50 miles of the SVRA (Appendix B). Based on this
information, estimated emissions from mobile sources are summarized in Table 3.2‐3.
TABLE 3.2­3. EXISTING EMISSIONS 1 (LBS/DAY) FROM MOBILE SOURCES DURING THE PEAK
WEEKEND DAY
Mobile Source ROG NOX CO PM10 PM2.5
Visitor vehicles 7.78 7.63 85.53 47.47 4.61
OHVs 30.48 1.21 148.10 360.84 35.49
Total emissions 38.26 8.84 233.63 408.31 40.10
Notes: CO = carbon monoxide; lbs/day = pounds per day; NOX = Oxides of Nitrogen; OHV = off‐highway vehicle; PM10
= particulate matter 10 microns in diameter or less; PM2.5 = particulate matter 2.5 microns in diameter or less; ROG =
reactive organic gases.
1 Emissions modeled using the URBEMIS2007, OFFROAD2007, and EMFAC2007 computer models. See Appendix C
for calculations. Assumes an average of 1.5 hours of OHV riding at an average of 15 mph per OHV (i.e. 22.5 miles
per OHV per day).
Source: Appendix C; data modeled by AECOM in 2011
The majority of the Clay Pit SVRA riding area is composed of clay soils with loose gravel, silt, and
cobbles. OHV use on loose soil generates dust during the dry summer months. This dust includes
fugitive PM10 and PM2.5. Temperature inversions in the valley that create a stable atmosphere, and
Clay Pit State Vehicular Recreation Area
February 2012 3.2-4 Draft EIR