COMMISSION

y the United States Environmental Protection Agency (EPA) that apply to new
diesel engines used in off-road equipment. Tier 4 requires manufacturers to reduce
the levels of particulate matter and oxides of nitrogen (NOx) to a level that is
50-96 percent lower than the existing generation of diesel engines. The new Tier 4
snow grooming tractor at Bucks Lake is the first of its type in North America.
Tier 4 diesel powered snow grooming tractor
Groomed trail
1.4 By 2013, implement a sound level management program with the
aim of reducing sound levels generated from vehicles recreating
off-highway.
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OHMVR Division resource specialists contracted with DPS Technical, Inc. for a pilot
ambient background sound quality program at Oceano Dunes SVRA and Prairie
City SVRA.
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OHMVR Division outreach efforts include
promotion of zero emission electric OHVs.
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As part of SVRA General Plan development,
comprehensive sound studies are conducted to
assist in the development of operational goals
and guidelines aimed at reducing SVRA sound
emissions.
Zero emission electric dirt bike
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Hollister Hills SVRA has had an ambient noise monitoring program on the
boundaries of the SVRA since 2002. Initially eight locations were monitored
multiple times per year to get a true baseline of the ambient noise levels. This has
evolved into a program that focuses on selected locations that are more sensitive
or where noise reduction management practices have been implemented to ensure
compliance. The monitoring sessions are staffed so that they can identify the cause
of any spikes, which are annotated on a strip sheet. The monitoring calendar is
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California State Parks, Off-Highway Motor Vehicle Recreation Commission